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The 


(Jrientation    of  iDuildings 


or 


Planning  for  Sunlight 


by 
IVilliam  Atkinson 

Fellow  of  the  Boston  Society  of  Architects 


FIRST  EDITION 
First  Thousatid 


NEW  YORK 

JOHN    WILEY  &  SONS 

London :  CHAPMAN  ©•>  HALL,  Limited 
IQL2 


.    Copyright,  191 2, 

BY 

WILLIAM  ATKINSON 


Entered  at  Stationers'  Hall,  London 


Stanbopc  lPreas 

F,   H.  GILSOH     COMPANY 
BOSTON,     U.S.A. 


In  Memory  of 
J.  Truman  Burdick 


Digitized  by  the  Internet  Archive 

in  2010  with  funding  from 

Open  Knowledge  Commons 


http://www.archive.org/details/orientationofbuiOOatki 


PREFACE 


The  purpose  of  this  book  is  to  set  forth  the  principles 
which  ought  to  govern  the  planning  of  buildings  with  re- 
spect to  sunlight,  a  subject  to  which  very  little  attention 
has  been  given. 

Several  years  ago,  in  an  essay  on  hospital  construction,1 
I  wrote  as  follows:  "To  study  properly  the  question  of 
sunlight,  a  sun  plan  of  the  buildings  must  be  drawn,  and 
their  positions  considered  with  respect  to  the  shadows  they 
cast  upon  each  other  and  upon  the  ground."  This  state- 
ment describes  very  well  the  general  method  of  study  which 
I  have  followed  in  my  investigations,  the  results  of  which 
are  now  for  the  first  time  presented  to  the  public  in  a 
complete  form. 

I  had  begun  my  study  of  orientation  with  hospitals  espe- 
cially in  mind,  but  I  soon  realized  that  the  general  principle 
of  planning  with  reference  to  sunlight  was  of  fundamental 
importance  in  the  design  of  all  buildings,  and  especially  in 
the  planning  and  laying  out  of  cities.  In  this  connection  I 
may  mention  that  a  series  of  diagrams  made  by  me,  at  the 
request  of  a  committee  interested  in  securing  new  legisla- 
tion regulating  the  height  of  buildings  in  Boston  in  1904, 
was  of  great  service  in  showing  the  effect  of  tall  buildings 

1  "Small  Hospitals,"  by  A.  Worcester,  M.D.,  and  "Suggestions  for  Hospital 
Architecture,"  by  William  Atkinson,  Architect,  New  York,  John  Wiley  &  Sons, 
1894. 

v 


VI  PREFACE 

in  overshadowing  and  shutting  out  the  sunlight  from  the 
streets.  Another  series  of  street  diagrams,  first  shown  at  a 
lecture  given  by  me  before  the  Society  of  Arts,  at  the  Mas- 
sachusetts Institute  of  Technology,  has  been  reprinted  by 
permission  in  a  recent  English  book  on  city  planning. 
Some  of  my  earlier  studies  in  orientation,  originally  pub- 
lished in  the  National  Hospital  Record,  have  been  twice  re- 
printed in  The  Brickbuilder  magazine,  and  also  embodied, 
by  permission,  in  a  recent  American  book  on  hospital  con- 
struction. 

All  of  which  has  encouraged  me  to  believe  that  a  more 
complete  presentation  of  the  subject,  in  book  form,  would 
not  be  without  interest  to  the  public. 

In  my  first  chapter  I  have  included  so  much  of  the  ele- 
ments of  astronomy  as  is  necessary  to  a  clear  understanding 
of  the  apparent  motion  of  the  sun,  and  the  variations  in 
the  angles  of  sunlight  at  the  different  seasons.  I  have  also 
described  the  method  of  the  stereographic  projection,  by 
which  the  angles  of  sunlight  may  easily  be  obtained,  for 
any  season  of  the  year,  and  for  any  latitude. 

The  second  chapter  deals  with  the  distribution  of  sun- 
light upon  the  exterior  of  buildings,  and  its  admission  to 
the  interior,  through  windows. 

In  this  chapter  I  have  developed  the  method  of  the 
"shadow  curve"  and  the  "area  of  complete  shadow,"  an 
application  of  the  principles  of  descriptive  geometry  to  the 
recording  of  transitory  occurrences,  which,  as  far  as  I  am 
aware,  is  new.  General  principles  for  the  planning  and 
placing  of  buildings  are  given  as  far  as  it  has  seemed 
desirable.     It  is,  however,  to  be  understood  that,  for  the 


PREFACE  Vll 

best  results,  each  case  must  be  studied  as  a  separate  prob- 
lem, with  reference  to  local  conditions,  and  especially  with 
reference  to  the  latitude  of  the  place.  In  connection  with 
the  study  of  windows  an  account  is  given  of  my  experi- 
ments with  the  "sun  box,"  an  apparatus  devised  by  me  to 
test  the  practical  effect  of  different  window  exposures. 

My  third  chapter  is  devoted  to  hospitals.  In  it  I  have 
discussed  the  vexed  question  of  the  best  orientation  for 
hospital  ward  pavilions  and  have  ventured  to  make  recom- 
mendations in  this  regard  at  variance  with  common  prac- 
tice. I  have  also  presented  a  plan  for  a  new  type  of  hospital 
building  especially  designed  to  meet  the  needs  of  modern 
medical  treatment. 

The  last  chapter  is  concerned  with  the  distribution  of 
sunlight  in  streets,  as  affected  by  their  direction  and  width, 
and  the  height  of  the  buildings  upon  them.  In  an  appendix 
I  have  given  in  full  the  building  law  of  Paris  regulating  the 
height  of  buildings  and  a  synopsis  of  the  regulations  of 
some  American  cities  in  this  matter. 

While  the  working  out  of  the  diagrams  and  the  calcula- 
tion of  the  tables  has  been  a  matter  of  pure  mathematics, 
admitting  but  one  result,  the  conclusions  to  be  drawn  from 
them  are  to  some  extent  a  matter  for  individual  judgment. 

It  is  therefore  fitting  that  I  should  give  here  a  statement 
of  the  premises  on  which  my  recommendations  are  based. 

I  have  assumed  that  it  is  desirable,  in  our  climate,  that 
all  buildings  in  which  human  beings  dwell  or  work  should 
have  all  of  their  exterior  walls  exposed  to  direct  sunlight 
at  some  time  during  the  day  throughout  the  year,  and  that 
the  surfaces  of  streets,  alleys,  areas,  courtyards,  and  other 


Vlll  PREFACE 

spaces  in  and  around  buildings  should  also  be  exposed  as 
much  as  possible  to  the  action  of  direct  sunlight. 

In  regard  to  windows,  I  have  assumed  that  as  much  direct 
sunlight  as  possible  is  desirable  through  them  during  that 
period  of  the  year  in  which  they  are  customarily  kept 
closed.  On  the  other  hand,  during  the  hot  season,  when 
windows  may  be  open  day  and  night,  and  the  sun-purified 
air  brought  in  from  outside  by  natural  means,  I  have 
assumed  that  direct  sunlight  through  windows  is  rather  to 
be  avoided  than  sought  after. 

The  function  of  sunlight  in  promoting  healthy  condi- 
tions, and  its  use  as  a  therapeutic  agent,  may  only  be 
authoritatively  stated  by  sanitarians  and  medical  men 
who  have  given  special  study  to  this  question,  and  I  can  do 
no  more  than  refer  those  who  may  wish  to  pursue  this 
branch  of  the  subject  to  the  work  of  the  German  and 
Danish  investigators,  a  full  account  of  which  may  be 
found  in  Luft-und  Sonnenbdder ,  by  Dr.  Julian  Marcuse, 
Stuttgart,  1907. 

The  diagrams  for  this  book  have  been  engraved  by  the 
wax  process  from  drawings  made  by  me,  and  the  few  which 
have  appeared  in  former  published  articles  have  been  care- 
fully revised  and  redrawn. 

Boxford,  Mass., 
October,  191 1. 


CONTENTS 


CHAPTER   I 

THE  ASTRONOMICAL  DATA 

Sunlight  a  requisite  for  healthy  buildings.  —  An  elementary  knowledge  of  as- 
tronomy necessary  for  intelligent  sun-planning.  —  The  angles  of  sunlight  at  the 
different  seasons  and  in  different  latitudes.  —  Calculation  of  the  angles  of  sun- 
light by  the  stereographic  projection.  —  By  spherical  trigonometry.  —  Table  of 
sunlight  angles. 

CHAPTER  II 

SHADOW  DIAGRAMS 

Shadows  of  the  cube.  —  Orientation  of  the  Swiss  house.  —  Shadow  curves  of 
the  cube.  —  Theory  of  the  area  of  complete  shadow.  —  The  area  of  complete 
shadow  as  applied  to  the  study  of  fundamental  types  of  building  plan.  —  Sunlight 
admitted  by  windows.  —  The  visual  angle  of  windows.  —  Quantity  of  sunlight 
admitted  by  windows.  —  Heating  effect  of  sunlight.  —  The  solar  constant.  — 
The  sun  box.  —  Sun-box  records. 

CHAPTER  III 

HOSPITALS 

The  orientation  of  ward  pavilions.  —  Different  views  upon  the  subject.  — 
Recommendations  of  the  author.  —  The  typical  ward  pavilion.  —  Its  unsuit- 
ability  to  modern  conditions.  —  A  new  type  of  ward  needed.  —  Description  of  the 
pyramidal  type  of  ward. 

CHAPTER  IV 

STREETS 

Angles  of  sunlight  in  streets.  —  Sunlight  curves  in  streets.  —  The  orientation  of 
streets.  —  Horace  Bushnell's  theory.  — ■  The  height  of  buildings.  —  European 
building  regulations.  —  The  law  of  ancient  lights.  —  Building  law  recommended 
by  the  author.  —  The  skyscraper  and  the  street. 

APPENDIX  A 

Sun  tables  for  London  and  New  Orleans. 

APPENDIX  B 

Building  laws  of  Paris  regulating  the  height  of  buildings. 

APPENDIX  C 

Building  laws  of  American  cities  regulating  the  height  of  buildings. 


LIST   OF   ILLUSTRATIONS 


CHAPTER  I 

Fig.  Page 

i.    Cross  sections  of  the  visible  celestial  sphere 3 

2.  Apparent  orbits  of  the  sun  at  the  different  seasons 6 

3.  Paths  of  the  sun  at  intermediate  periods 7 

4.  Stereographic  projection  of  the  visible  celestial  sphere 9 

5.  Construction  of  the  stereographic  projection.  —  First  step 12 

6.  Construction  of  the  stereographic  projection.  —  Second  step 14 

7.  Construction  of  the  stereographic  projection.  —  Third  step 16 

CHAPTER  II 

8.  Shadows  of  the  cube 20 

9.  Shadows  of  the  cube 21 

10.  Shadows  of  the  cube 22 

11.  Plan  of  typical  Swiss  dwelling 23 

12.  Shadow  curves  of  the  cube.     Winter  solstice 25 

13.  Shadow  curves  of  the  cube.     Winter  solstice 26 

14.  Shadow  curves  of  the  cube.     Equinoxes 27 

15.  Shadow  curves  of  the  cube.     Equinoxes 28 

16.  Shadow  curves  of  the  cube.     Summer  solstice 29 

17.  Shadow  curves  of  the  cube.     Summer  solstice 30 

18.  Areas  of  complete  shadow:  single  straight  block 32 

19.  Areas  of  complete  shadow:  L  plan 33 

20.  Areas  of  complete  shadow:  U  plan 34 

21.  Method  of  obtaining  the  area  of  complete  shadow 36 

22.  Shadow  curves  of  cube  and  prism  at  winter  solstice 37 

23.  Maximum  areas  of  complete  shadow  for  the  L  and  U  plans 38 

24.  Effect  of  increase  of  height  upon  the  area  of  complete  shadow 39 

25.  Good  and  bad  arrangement  of  L 41 

26.  Application  of  the  test  of  the  area  of  complete  shadow 42 

27.  Shadows  of  the  single  straight  block.     Axis  N.  and  S 44 

xi 


Xll  LIST  OF  ILLUSTRATIONS 

Fig.  Page 

28.  Shadows  of  the  single  straight  block.     Axis  E.  and  W 45 

29.  Shadows  of  the  single  straight  block.     Axis  N.  E.  and  S.  W 46 

30.  Visual  angle  of  ordinary  window 47 

31.  Visual  angle  of  mediaeval  window 48 

32.  Wall  section  with  beveled  piers 49 

33.  Window  illumination:  winter  solstice 50 

34.  Window  illumination:  equinoxes S1 

35.  Window  illumination:  summer  solstice 52 

36.  Cross  sections  of  sunlight  prism 53 

37.  Change  in  area  of  sunlight  prism:  winter  solstice 55 

38.  Change  in  area  of  sunlight  prism:  equinoxes 56 

39.  Change  in  area  of  sunlight  prism:  summer  solstice 57 

40.  Windows :  obstructed  outlook 59 

41.  Obstructed  outlook:  stereographic  projection 61 

42.  Change  in  area  of  sunlight  prism:  obstructed  outlook 62 

43.  Cross  section  of  sun  box 64 

44.  Photograph  of  sun  box 65 

45.  Sun  box  records 76 

46.  Sun  house 77 

CHAPTER  III 

47.  Ward  pavilion:  open-ended  type 80 

48.  French  method  of  hanging  outside  blinds 84 

49.  Economy  of  two-story  type  of  pavilion 86 

50.  Section  of  ward  with  ridge  ventilation 88 

51.  Types  of  ward  pavilions 89 

52.  Grouping  of  ward  units:  Virchow  Hospital 91 

53.  Grouping  of  ward  units 92 

54.  Grouping  of  ward  units 93 

55.  Grouping  of  ward  units 95 

56.  Elevation  of  Virchow  ward  unit 97 

57.  Pyramidal  type  of  ward  construction 98 

58.  Pyramidal  ward  unit:  first-floor  plan 99 

59.  Pyramidal  ward  unit:  second-floor  plan 100 

60.  Pyramidal  ward  unit:  third-floor  plan 101 

61.  Pyramidal  ward  unit:  shadow  diagram 102 


LIST  OF  ILLUSTRATIONS  xm 

Fig.  Page 

62.  Pyramidal  ward  unit:  shadow  diagram 103 

63.  Pyramidal  ward  unit:  shadow  diagram 104 

64.  Pyramidal  ward  unit:  general  plan 1 06 

65.  Pyramidal  ward  unit:  elevation 107 

CHAPTER  IV 

66.  Angles  of  sunlight  in  streets in 

67.  Angles  of  sunlight  in  streets 112 

68.  Angles  of  sunlight  in  streets 113 

69.  Method  of  obtaining  sunlight  curves 114 

70.  Sunlight  curves:  streets 116 

71.  Building  law  of  Paris 119 

72.  Typical  cornice  section 122 

73.  Proposed  building  law 123 

74.  The  skyscraper  and  the  street 124 


THE  ORIENTATION  OF 
BUILDINGS 


CHAPTER   I 

THE   ASTRONOMICAL   DATA 

Unquestionably  one  of  the  first  requisites  for  a  healthy 
building  is  abundance  of  sunlight.  Not  only  the  exterior 
wall  surfaces  of  buildings,  but  also  the  surfaces  of  the 
ground  around  them,  should  have  the  direct  rays  of  the 
sun  for  as  long  a  time  as  possible  each  day. 

"Second  only  to  air,  is  light  and  sunshine  essential  for 
growth  and  health;  and  it  is  one  of  Nature's  most  power- 
ful assistants  in  enabling  the  body  to  throw  off  those 
conditions  which  we  call  disease.  Not  only  daylight, 
but  sunlight;  indeed,  fresh  air  must  be  sun- warmed,  sun- 
penetrated  air.  The  sunshine  of  a  December  day  has 
been  recently  shown  to  kill  the  spores  of  the  anthrax 
bacillus."    (Healthy  Hospitals,  Sir  Douglas  Gal  ton,  Oxford, 

1893). 

To  secure  sunlight  in  fullest  measure  requires  careful  and 
intelligent  planning  with  this  end  in  view.  It  is  necessary 
for  such  a  study  to  have  at  hand  a  table,  giving  the  angles 
of  sunlight  at  the  different  hours  of  the  day  and  at  the 
different  seasons  of  the  year,  for  the  particular  latitude  in 
question. 


ORIENTATION  OF  BUILDINGS 


In  this  chapter  I  shall  describe  one  method  by  which 
such  a  table  may  be  prepared. 

In  all  of  the  operations  of  practical  astronomy,  as  in 
the  calculation  of  position  of  ships  at  sea,  or  in  deter- 
minations of  latitude  and  longitude  upon  land,  it  has 
been  found  best  to  go  back  to  the  conceptions  of  the 
first  astronomers,  who  imagined  the  earth  to  be  the  cen- 
ter of  the  universe,  and  the  celestial  bodies  to  revolve 
around  it. 

And  thus  has  survived  the  ancient  fiction  of  the  "  celestial 
sphere." 

Viewing  the  heavens  on  a  starry  night,  the  whole  firma- 
ment seems  slowly  to  revolve,  successively  bringing  into 
view,  above  the  eastern  horizon,  one  constellation  after 
another. 

If,  by  magic  power,  the  sun's  light  could  be  dimmed  so 
that  the  stars  should  be  visible  in  the  daytime,  he  would 
appear,  like  them,  to  be  fixed  in  the  celestial  sphere,  and 
to  turn  with  the  constellations  in  their  uniform  diurnal 
motion  around  the  pole. 

But  if  we  could  extend  our  observations  over  a  period 
of  several  weeks,  we  should  observe  that  the  sun  was  slowly 
changing  his  position  among  the  stars,  passing  in  the 
course  of  a  single  year  through  the  successive  constella- 
tions of  the  zodiac,  in  summer  north  of  the  celestial  equator, 
in  winter  south. 

But  this  change  in  the  apparent  position  of  the  sun  is  so 
slow  that  for  any  single  day  it  may  be  disregarded,  and 
his  position  for  that  day  considered  as  fixed  in  the  celestial 
sphere. 


THE  ASTRONOMICAL  DATA 


Z    S 


s'  o  w' 

NEW  ORLEANS 

Fig.  i.  —  Cross  sections  of  the  visible  celestial  sphere,  showing  the  path  of  the 
sun  at  the  solstices,  and  at  the  equinoctial  periods,  for  different  latitudes. 


ORIENTATION  OF  BUILDINGS 


Fig.  I  shows  in  cross  section  that  part  of  the  celestial 
sphere  which  is  above  the  horizon,  at  the  latitudes  respec- 
tively of  London  (Lat.  5i°-3o'  N.),  Boston  (Lat.  /\2°-22'  N.), 
and  New  Orleans  (Lat.  3o°-o'  N.). 

In  tnese  diagrams  H'H  represents  the  plane  of  the 
horizon;  0  the  position  of  the  observer;  P  the  celestial 
north  pole;  Z  the  zenith,-  and  SS\  EO,  and  WW  the 
apparent  paths  of  the  sun  at  the  periods  of  the  summer 
solstice,  the  equinoxes,  and  the  winter  solstice,  respectively. 

It  is  evident  that  the  altitude  of  the  sun,  at  noon,  at  the 
periods  of  the  year  referred  to,  may  be  obtained  directly 
from  the  diagrams,  being  given  by  the  angles  HOS,  HOE, 
and  HOW,  for  the  summer  solstice,  the  equinoxes,  and  the 
winter  solstice,. respectively. 

It  will  be  observed  that  these  angles  are  less  in  the  more 
northerly  latitudes,  and  that  the  path  of  the  sun  inclines 
more  and  inore  toward  the  horizon. 

This  decrease  in  the  altitude  of  the  sun  is  accompanied 
with  an  increasing  divergence  between  the  extreme  points 
of  sunrise  and  sunset,  so  that  the  days  in  summer  are 
much  longer,  and  in  winter  much  shorter,  in  the  countries 
of  the  far  north,  than  in  those  which  are  near  the  equator. 

At  latitude  \2°-o'  N.  (approximately  the  latitude  of 
Boston,  Mass.)  the  sun  rises  on  the  longest  day  of  the  year 
about  32I0  north  of  east  and  sets  at  an  equal  angle  north 
of  west,  reaching  at  noon  an  altitude  of  yi°-2yr  above  the 
horizon. 

On  the  shortest  day  of  the  year  he  rises  about  32§°  south 
of  east  and  sets  at  an  equal  angle  south  of  west,  reaching 
at  noon  an  altitude  of  only  24°-33'  above  the  horizon. 


THE  ASTRONOMICAL  DATA  5 

At  the  two  periods  of  the  year  when  day  and  night 
are  of  equal  length  he  rises  in  the  east  and  sets  in  the 
west,  reaching  at  noon  an  altitude  of  48°-o/  above 'the 
horizon. 

The  perspective  diagrams  of  Fig.  2  will  give  the  student 
an  easily-remembered  mental  image  of  the  path  of  the  sun 
at  these  periods. 

The  horizontal  circle  represents  the  horizon;  the  inclined 
circle  the  path  of  the  sun,  and  the  diverging  lines  the  direc- 
tion of  the  sun's  rays  at  the  different  hours  of  the  day. 

It  will  be  noted  that  at  the  period  of  the  equinoxes  the 
trace  of  the  sun's  rays  describes  a  plane;  at  the  period  of 
the  summer  solstice  a  hollow  cone,  and  at  the  period  of 
the  winter  solstice  a  convex  cone. 

His  path  at  intermediate  periods  may  be  pictured  by  the 
aid  of  the  following  diagram  (Fig.  3)  which  gives  his  posi- 
tion at  intervals  of  one  month  apart  throughout  the  year. 

It  will  be  observed  from  this  diagram  that  the  path  of 
the  sun  during  the  four  months  from  April  21  to  August  21 
resembles  more  nearly  his  path  at  the  summer  solstice 
than  his  path  at  the  equinoxes,  and  similarly  his  path 
during  the  four  months  from  October  21  to  February  21 
more  nearly  his  path  at  the  winter  solstice  than  his  path 
at  the  equinoxes. 

This  must  be  borne  in  mind  in  studying  the  various 
shadow  diagrams  which  are  given  later  in  this  book.  Those 
which  are  drawn  for  the  period  of  the  winter  solstice  may 
be  taken  as  typical  of  the  four  months  from  October  21  to 
February  21;  those  which  are  drawn  from  the  period  of 
the  summer  solstice  of  the  four  months  from  April  21   to 


ORIENTATION  OF  BUILDINGS 


Sunrise 


ii   m   t 


"Sunset 


Sunrise     E 


XI     HI 


W      Sunset 


11      Hi 


Sunset 


Fig.  2.  -  Perspective  diagrams  showing  the  apparent  path  of  he  sun, «dtib 
andes  of  sunlight  at  the  different  hours  of  the  day,  for  Lat.  42  -o  N.  The  upper 
dLtim  i^ra  for  the  summer  solstice,  the  middle  diagram  for  the  vernal  and 
autumnal  equinox,  and  the  lower  diagram  for  the  waiter  solstice. 


THE   ASTRONOMICAL  DATA 


August  21 ;  and  those  which  are  drawn  for  the  period 
of  the  equinoxes  of  the  two  months  from  February  21 
to  April  21,  and  the  two  months  from  August  21  to 
October  21. 

The  position  of  the  sun  with  respect  to  the  observer  is 
generally  expressed  in  terms  of  azimuth  and  altitude. 


Fig.  3.  —  Cross-section  of  the  visible  celestial  sphere  showing  the  path  of  the 
sun  at  periods  one  month  apart  throughout  the  year.  Lat.  42°-o'  X.  Actually 
the  declination  of  the  sun  on  May  21  does  not  exactly  coincide  with  his  declina- 
tion on  July  21,  although  it  is  so  represented  in  the  diagram.  A  similar  observation 
applies  to  the  other  dates  which  are  grouped  in  pairs.  The  differences,  however, 
are  so  slight  that  it  would  be  difficult  to  represent  them  at  the  scale  at  which  the 
drawing  is  made. 


The  latter  term  requires  no  explanation,  but  the  mean- 
ing of  "azimuth"  may  not  be  so  generally  understood. 
It  may  preferably  be  explained  by  an  example  rather  than 
a  definition. 

Imagine  a  stick  set  upright  in  level  ground  in  the  sun- 
light.    The   deviation   of   the   shadow   cast   by   the   stick 


ORIENTATION   OF  BUILDINGS 


from  a  true  north  and  south  direction  is  the  azimuth  of 
the  sun  at  that  moment. 

Knowing  the  distance  of  the  sun  north  or  south  from 
the  equator  (which  information  may  be  obtained  from  the 
almanac)  the  azimuth  and  altitude  for  any  particular  day 
may  be  calculated  by  spherical  trigonometry. 

The  desired  data  may  also  be  obtained  very  simply  and 
easily,  and  with  sufficient  accuracy  for  our  purposes,  by 
the  stereographic  projection. 

To  one  who  understands  perspective,  the  stereographic 
projection  presents  little  difficulty,  as  it  is  virtually  the 
method  of  linear  perspective  applied  to  the  representation  of 
the  sphere,  but  with  this  difference,  that  the  drawing  when 
completed  is  viewed  from  behind  the  picture  plane,  instead 
of  in  front  of  it,  as  in  ordinary  perspective. 

It  possesses  two  properties  which  make  it  especially 
useful;  the  first  being  that  all  circles  of  the  sphere  are 
projected  as  circles  or  as  straight  lines,  and  hence  may 
be  drawn  with  compasses  and  ruler; 'and  the  second  being 
that  the  angle  made  by  the  crossing  of  two  circles  upon 
the  surface  of  the  sphere  is  the  same  as  the  angle  made  by 
their  projections. 

The  statement  that  by  the  aid  of  the  stereographic  pro- 
jection one  may,  with  a  few  hours'  labor,  construct  a 
diagram  which  will  give  the  position  of  the  sun  at  each 
hour  of  the  day  for  any  period  of  the  year  desired,  and  for 
any  latitude,  should  be  sufficient  to  induce  the  student  to 
master  its  principles. 

Such  a  diagram,  drawn  for  latitude  42°-o'  N.,  is  shown 
in  Fig.  4. 


TEE  ASTRONOMICAL   DATA 


This  is  a  stereographic  projection  of  the  celestial  sphere, 

taken  upon  the  plane  of  the  horizon,  which  is  represented 

by  the  circle  N,  E,  S,  W,  these  letters  being  placed  at  the 

four  cardinal  points. 

N 


B2, 


w 


¥-\-\-\yi-X—\ — 


Bl 


/      / 


/         / 


\A// 


-n 


FlG.  4.  —  Stereographic  projection  of  the  visible  celestial  sphere,  upon  the  plane 

of  the  horizon. 

The  circular  arc  WE  is  the  projection  of  the  celestial 
equator,  which  is  the  path  of  the  sun  at  the  period  of  the 
equinoxes. 

The  arc  of  considerably  greater  curvature  to  the  north 
is  the  projection  of  the  tropic  of  Cancer,  which  is  the  path 


IO  ORIENTATION  OF  BUILDINGS 

of  the  sun  at  the  summer  solstice,  while  the  more  flat- 
tened and  shorter  arc  to  the  south  is  the  projection  of  the 
tropic  of  Capricorn,  which  is  the  path  of  the  sun  at  the 
winter  solstice. 

The  twelve  circles  converging  toward  the  upper  part  of 
the  diagram  are  the  projections  of  the  celestial  meridians, 
or  hour  circles,  150  apart. 

These  hour  circles  may  be  conceived  of  as  a  gigantic 
cage  or  framework,  fixed  in  position,  and  serving  as  a 
system  of  celestial  verniers,  to  mark  the  passage  of  the 
heavenly  bodies,  which  are  carried  past  them  with  the 
revolution  of  the  sphere. 

The  passage  of  the  sun  across  the  successive  hour  circles 
marks  the  hours  of  the  day  as  shown  by  a  sundial.  Con- 
sequently the  intersection  of  any  hour  circle  with  the  circle 
representing  the  path  of  the  sun  is  the  stereographic  pro- 
jection of  the  sun's  position  for  the  corresponding  hour 
and  period  of  the  year. 

And  from  this  projection  the  azimuth  and  altitude  may 
readily  be  found. 

For  instance,  the  dotted  line  OB  drawn  through  the 
intersection  of  the  11-0' clock  hour  circle  and  the  celestial 
equator  gives  the  azimuth  of  the  sun  at  11  a.m.  {solar 
time)  at  the  period  of  the  equinoxes,  and  the  dotted  line 
OB  1  drawn  through  the  intersection  of  the  1-0'clock  hour 
circle  and  the  tropic  of  Capricorn  gives  the  azimuth  of 
the  sun  at  1  p.m.  on  December  21st,  and  the  dotted  line 
OB2  drawn  through  the  intersection  of  the  6-o'clock  hour 
circle  and  the  tropic  of  Cancer  gives  the  azimuth  of  the 
sun  at  6  p.m.  on  June  21st. 


THE   ASTRONOMICAL   DATA  II 


The  altitude  is  obtained  by  a  simple  construction.  For 
example,  the  angle  EOD  is  the  altitude  of  the  sun  at 
II  A.M.  at  the  period  of  the  equinoxes  and  is  found  by 
measuring  off  on  the  line  OE  the  distance  OC  equal  to  OA 
and  drawing  the  line  SC  intersecting  the  enclosing  circle 
at  the  point  D. 

To  explain  more  fully  the  construction  of  the  diagram, 
an  example  will  be  given  and  worked  out. 

Let  it  be  required  to  find  the  position  of  the  sun  at 
10  a.m.,  solar  time,  April  16,  Lat.  30°-o'  N. 

Draw  a  cross  section  of  the  visible  celestial  sphere,  as 
shown  in  the  upper  part  of  Fig.  5. 

HH  is  the  horizon,  0  the  position  of  the  observer,  and 
Z  the  zenith.  Through  O  draw  the  line  POP'  making 
an  angle  of  30°-o'  with  the  horizon. 

P  is  the  celestial  north  pole,  for  it  is  shown  in  astronomy 
that  the  altitude  of  the  pole  is  equal  to  the  latitude  of  the 
place. 

Draw  OE  at  right  angles  to  POP. 

It  represents  the  celestial  equator. 

From  the  point  E  lay  off  the  arc  ES  equal  to  the 
declination  of  the  sun  on  the  date  required.  This  we 
find  from  the  almanac  (for  19 10)  to  be  9°-59'  for 
April  16. 

Draw  SM  parallel  to  OE.  It  represents  the  path  of  the 
sun  above  the  horizon  at  this  period. 

The  projection  is  made  upon  the  plane  of  the  horizon, 
and  the  station  point  is  upon  the  surface  of  the  sphere 
vertically  below  the  zenith,  at  N. 

Any  point  upon  the  surface  of  the  sphere  is  projected 


12 


ORIENTATION  OF  BUILDINGS 


Fig.  5.  —  Construction  of  the  stereographic  projection,  first  step.  The  upper 
part  of  the  diagram  is  a  cross  section  of  the  celestial  sphere;  the  lower  part  its  pro- 
jection upon  the  plane  of  the  horizon. 


THE   ASTRONOMICAL  DATA  1 3 

by  joining  it  to  the  station  point  by  a  straight  line  and 
the  point  in  which  this  line  pierces  the  picture  plane  HH 
is  the  projection  required. 

The  enclosing  circle  is  the  horizon,  which  is  drawn 
without  change  since  it  lies  in  the  plane  of  the  projection. 

The  circle  MS  may  now  be  projected. 

It  is  evident  that  M'  and  M'  are  the  points  at  which 
this  circle  cuts  the  horizon,  and  that  S'  is  the  projection 
of  the  point  S. 

Through  these  three  points  draw  the  arc  of  a  circle. 

It  is  the  projection  required,  for  it  is  a  theorem  of  the 
stereographic  projection  that  all  circles  of  the  sphere  are 
projected  as  circles  or  portions  of  circles,  with  the  exception 
of  those  which  pass  through  the  station  point,  which  are 
obviously  projected  as  straight  lines. 

An  example  of  the  latter  is  the  meridian  or  12-o'clock 
hour  circle,  which  is  projected  as  the  straight  line 
H'S'H'. 

To  find  the  point  upon  the  arc  M'S'M'  where  the  sun 
is  at  10  a.m.  it  is  necessary  to  project  the  io-o'clock  hour 
circle. 

(For  the  sake  of  clearness  the  operation  is  shown  in  a 
separate  diagram,  Fig.  6.) 

Since  all  the  hour  circles  pass  through  the  north  and 
south  poles,  we  have  at  once,  in  the  projections  of  the 
poles  (at  PP  and  P'P'),  two  points  of  our  required  projec- 
tion. 

It  remains  to  find  the  center. 

The  line  LT,  equidistant  from  PP  and  P'P',  contains 
the  centers  of  all   circles  passing  through  those  points. 


14 


ORIENTATION   OF  BUILDINGS 


1 
1 

Is 

\ 
\ 
\ 

\ 

/  s 

\ 

S             S 

"■--^r- 

FlG.  6.  —  Construction  of  the  stereographic  projection,  second  step. 


THE  ASTRONOMICAL  DATA  15 

To  find  the  point  upon  this  line  which  is  the  center  of 
the  projected  10-0'clock  hour  circle,  we  avail  ourselves  of 
the  second  theorem  of  the  stereographic  projection,  which 
is  that  the  angle  made  by  two  circles  upon  the  surface 
of  the  sphere  is  the  same  as  the  angle  made  by  their 
projections. 

Now  the  10-0'clock  hour  circle  makes  an  angle  of  300 
with  the  noon  circle,  or  meridian,  where  it  crosses  the 
latter  at  the  poles,  one  hour  being  equal  to  150. 

Consequently  a  line  drawn  through  PP,  the  projection 
of  the  north  pole,  and  making  an  angle  of  300  with  PP  P'P', 
the  projection  of  the  meridian,  is  a  tangent  to  the  pro- 
jection of  the  10-0'clock  hour  circle,  and  establishes  the 
center  of  the  latter  at  once,  at  the  point  T,  upon  the 
line  LT. 

The  circle  may  now  be  drawn. 

Superposing  the  two  circles  thus  obtained  in  one  diagram 
(Fig.  7),  their  intersection  at  A  is  the  projection  of  the  sun's 
position  and  the  angle  H'OX  is  the  true  bearing  or  azimuth 
of  the  sun  required. 

The  altitude  may  be  found  by  a  secondary  construction. 
(Lower  diagram  of  Fig.  7.) 

It  is  evident  that  the  straight  line  XAO  is  the  projection 
of  a  circle,  vertical  to  the  plane  of  the  horizon,  and  passing 
through  the  zenith  and  the  sun. 

The  sun's  altitude  is  measured  upon  this  circle,  upward 
from  the  horizon. 

Let  us  imagine  this  circle  to  be  revolved  into  the  plane 
of  the  horizon,  thus  bringing  the  station  point  to  the  posi- 
tion N  and  the  zenith  to  the  position  Z. 


:-' 


ORIENTATION   OF   BUILDINGS 


Fig.  7.  —  Construction  of  the  stereographic  projection,  third  step.  (The  point 
P  referred  to  in  the  test  is  the  projection  of  the  north  pole,  to  the  left  of  0,  on 
the  dotted  line  E'H'.j 


THE   ASTRONOMICAL   DATA 


17 


The  sun  lies  at  some  point  upon  this  circle.  To  find 
this  point  draw  the  line  NA  cutting  the  circle  at  K.  It 
is  the  point  required,  and  XOK  is  the  altitude  of  the  sun 
required. 

By  following  the  above  method  and  making  the  pro- 
jection at  a  large  scale  the  angles  may  be  found  with  suffi- 
cient accuracy  for  the  purposes  of  the  architect. 

To  obtain  the  result  by  calculation  involves  the  solution 
of  the  spherical  triangle  POA  of  which  the  two  sides  PA 
(the  north  polar  distance  of  the  sun),  PO  (the  co-latitude 
of  the  place),  and  APO  (the  assumed  hour  angle)  are 
known.     (Upper  diagram  of  Fig.  7.) 

Solving  for  the  angle  A  OP  and  the  third  side  AO  gives 
us  H'OX,  and  XA  the  azimuth  and  altitude  respectively. 

In  the  following  table  is  given  the  azimuth  and  altitude 
of  the  sun  for  420  north  latitude  at  each  hour  of  the  day 
for  the  typical  periods  of  the  year. 


TABLE    I 


Hour  angle. 


S-7  105 


7  -S 
It.  1     *5 


90 

75c 

6oc 

45 C 


Winter  solstice. 


Equinoxes. 


Azimuth.    ,    Altitude.       Azimuth.       Altitude. 


S^  -49 
4i°-38' 

29  °-  o' 

i4°-58' 

o°-  o' 


4-17 

I2°-28' 

i8°-55' 
23 °-  6' 
24°"33' 


90-0 
79°-5° 
68°-53 
56°-i3 
40°-47 
2i°-49 
o°-  o 


"  -  5 
2i°-49' 

3i°-42' 

40°-  4' 
45°-52' 
4S0-  o' 


Summer  solstice. 


Azimuth.       Altitude. 


H7°-io' 

5°-9' 

i°7°-52' 
98°-46' 
89°-i2' 
77°_5S 
6'2°-47' 
38°-36' 

i5°-27' 
26°-i7' 

37°-23' 

4S°-2  7' 

5S°-57' 
67°-38' 

o°-  0' 

7i°-27' 

Sunrise  and  sunset. 

4  h.  28  m. 
6  h.    0  m. 

570— 37'          o°— 0' 

90°-o' 

o°-o' 

7  h.  32  m. 

I22°-23' 

~°    «' 



1 8  ORIENTATION   OF  BUILDINGS 

EXPLANATION  OF  TABLE. 

The  first  column  gives  the  solar  time  expressed  in  hour  angles,  one  hour  being 
equal  to  15  degrees,  reckoning  either  way  from  noon.  For  instance,  the  hour  angle 
30  degrees  corresponds  to  10  a.m.  or  2  p.m.,  the  hour  angle  45  degrees  to  9  a.m. 
or  3  p.m.,  and  so  on.  Azimuth  is  east  of  south  for  the  forenoon  and  west  of  south 
for  the  afternoon. 

No  corrections  have  been  made  for  refraction,  the  effect  of  which  is  to  slightly 
increase  the  altitude  when  the  sun  is  near  the  horizon. 

This  table  is  the  basis  on  which  all  of  the  diagrams  in  this 
book  have  been  constructed. 

Similar  tables,  computed  for  the  latitudes  of  London  and 
New  Orleans,  will  be  found  in  the  appendix. 


CHAPTER   II 

Shadow  Diagrams 

As  the  first  example  of  the  application  of  the  data 
obtained  in  the  preceding  chapter,  let  us  consider  the 
shadows  cast  by  two  cubes,  one  of  them  placed  with  its 
four  sides  facing  the  cardinal  points,  and  the  other  with 
its  diagonal  upon  the  meridian. 

These  shadows  are  shown  in  Figs.  8,  9,  and  10  and  are 
given  for  each  hour  of  the  day  at  the  typical  periods  of 
the  year.1 

It  is  evident  that  in  the  first  position  the  north  face  of 
the  cube  receives  no  sunlight  during  one-half  the  year, 
from  the  autumnal  to  the  vernal  equinox,  whereas  in  the 
second  position  all  four  faces  receive  sunlight  at  some  por- 
tion of  each  day,  throughout  the  year. 

There  is  another  advantage,  not  inconsiderable,  in  the 
latter  arrangement,  since  in  this  position  the  cube  shades 
the  surface  of  the  ground  considerably  less  than  when  it 
is  placed  squarely  facing  the  cardinal  points. 

A  study  of  the  diagrams  will  make  this  apparent. 

It  will  be  noted  that  in  the  lower  diagrams  of  each 
figure  the  shadows  overlap  each  other  to  a  greater  extent 
than  they  do  in  the  upper  ones  and  furthermore  that  in 
the  lower  diagram  of  Fig.  8  there  is  a  triangular  area  which 
receives  no  sunlight  at  all. 

1  These  diagrams  and  all  those  which  follow  are  drawn  for  latitude  42°-o'  north. 

19 


Fig.  8.  —  Shadows  of  the  cube,  winter  solstice.     The  shaded  area  in  the  lower 
diagram  receives  no  sunlight.    Lat.  42°-o'  N.  20 


VIII  IX       X    XI  XII   I     II      III 


VIII  IX       X    XI  XII   I     II      III 


Fig.  9.  —  Shadows  of  the  cube,  autumnal  and  vernal  equinox.   Lat.  42°-o'  N. 


Fig.  io.  —  Shadows  of  the  cube,  summer  solstice.    Lat.  42°-o'  N.  22 


SHADOW   DIAGRAMS 


23 


The  advantage  of  placing  a  square  building  with  its 
diagonal  upon  the  meridian  was  long  ago  recognized  by 
the  mountain  dwellers  of  Switzerland. 

The  ground  plan  of  a  typical  Swiss  dwelling  is  shown 
in   Fig.    n.1 

It  will  be  observed  that  the  living  room  is  placed  in  the 
sunniest  corner  of  the  building,  with  its  windows  facing 
southeast  and  southwest. 


-1 

kwlllllllll 

r 

u 



1 

oo[ 

= 

J^>\ 

J\     - 

3 

=-l 

tf—  ■ 

'— J 

Fig.  11.  —  Ground  plan  of  Swiss  dwelling,  showing  the  customary  orientation. 
A  is  the  Living  Room. 


Referring  again  to  the  shadows  of  the  cube  it  will  be 
observed  that  at  the  equinoctial  periods  the  tips  of  the 
shadows  move  in  a  straight  line  from  west  to  east,  whereas 
at  all  other  seasons  they  describe  a  curve. 

A  further  study  of  the  diagrams  will  show  that  other 
curves  are  contained  in  them  besides  those  described  by 
the  tips  of  the  shadows,  and  in  one  of  the  diagrams  such 
a  curve  is  shown,  passing  through  certain  points  of  inter- 
section of  the  shadows,  those  points  having  been  selected 

1  Taken  from  Die  Holz-Architectur  der  Schweiz.  Gladbach.  Zurich  and 
Leipzig,  1885. 


24 


ORIENTATION   OF   BUILDINGS 


which  are  in  shadow  for  exactly  two  hours,  as,  for  instance, 
the  point  P,  which  first  comes  into  shadow  at  10  A.M., 
and  emerges  again  at  noon.  And  a  study  of  the  diagram 
(Fig.  8)  will  show  that  each  of  the  other  points  is  in 
shadow  for  the  same  length  of  time. 

Such  a  curve  may  be  called  a  "shadow  curve,"  and  the 
curve  of  our  figure  the  "two-hour  shadow  curve."  In  the 
same  way  we  might  draw  the  "three- hour"  and  the  "four- 
hour  shadow  curve,"  and  so  on,  until  our  original  drawing 
should  become  translated  into  a  new  and  strange  diagram, 
consisting  entirely  of  curves. 

,  It  is  in  this  manner  that  the  following  diagrams  have 
been  drawn  (Figs.  12  to  17). 

To  express  more  clearly  their  meaning,  the  zones  between 
the  curves  have  been  shaded  in  a  series  of  tints,  correspond- 
ing to  the  following  table: 


1 

— 

:1 
1 

■'■i 

4 

Area  in  sunlight  between  9  and  8  hours. 
Area  in  sunlight  between  8  and  7  hours. 
Area  in  sunlight  between  7  and  6  hours. 
Area  in  sunlight  between  6  and  5  hours. 
Area  in  sunlight  between  5  and  4  hours. 
Area  in  sunlight  between  4  and  3  hours. 
Area  in  sunlight  between  3  and  2  hours. 
Area  in  sunlight  between  2  and  1  hours. 
Area  in  sunlight  for  less  than  1  hour. 
Area  without  sunlight. 


These  diagrams  not  only  illustrate,  in  a  graphic  manner, 
the  effect  of  the  object  or  building,  in  shading  the  ground 
around  it,  but  they  also  indicate  the  distribution  of  sun- 


SHADOW   DIAGRAMS 


25 


26 


ORIENTATION   OF  BUILDINGS 


SHADOW  DIAGRAMS 


27 


28 


ORIENTATION  OF  BUILDINGS 


SHADOW   DIAGRAMS 


29 


3Q 


ORIENTATION   OF  BUILDINGS 


SHADOW  DIAGRAMS  31 


light  upon  the  vertical  surfaces,  or  walls,  of  the  building 
itself. 

In  the  same  manner  the  shadow  curves  of  any  object  or 
building  may  be  obtained. 

The  process  affords  a  useful  exercise  in  descriptive 
geometry,  and  the  results  are  interesting  and  instructive. 
To  reproduce  the  complete  series  of  shadow  curves  for 
each  type  of  object  or  building  which  we  shall  study 
would,  however,  require  an  unduly  large  number  of  dia- 
grams. 

It  becomes  desirable  therefore  to  devise  a  method 
which  will  present  the  subject  in  a  more  condensed 
form. 

Such  a  method  has  been  adopted  for  the  diagrams  which 
follow,  and  the  manner  of  their  construction  will  now  be 
explained. 

In  the  discussion  of  the  shadow  curves  of  the  cube,  it  was 
pointed  out  that  one  of  the  diagrams  differed  essentially 
from  the  others  in  that  it  disclosed  an  area  having  no  sun- 
light at  all  during  the  day. 

Such  an  area  will  be  called  an  area  of  complete  shadow 
and  may  be  defined  as  follows: 

The  area  of  complete  shadow  of  any  object  reposing 
upon  a  horizontal  plane  surface  is  that  portion  of  the 
object,  and  of  the  surface  upon  which  it  rests,  which  is 
continuously  in  shade  at  the  particular  period  of  the  year 
under  consideration,  and  an  area  of  perpetual  shadow  is  that 
portion  of  the  surface  which  receives  no  direct  sunlight 
at  any  time  during  the  year. 

It  is  evident  that  by  superposing  the  areas  of  complete 


32 


ORIENTATION   OF  BUILDINGS 


shadow  for  different  seasons,  we  may,  in  a  single  diagram, 
embrace  the  phenomena  of  an  entire  year. 

And  this  has  been  done  in  the  following  diagrams 
(Figs.  18,  19,  and  20)  in  which  the  waxing  and  the  wan- 
ing of  the  area  of  complete  shadow  is  shown  by  indicat- 
ing its  size  at  periods  one  month  apart  •  throughout  the 
year. 

These  diagrams  show  the  area  of  complete  shadow  for 
the  three  fundamental  types  of  building  plan:  the  single 
straight  block  (of  which  the  cube  is  a  particular  case), 

N 


Fig.  18.  —  Areas  of  complete  shadow;  single  straight  block.     Lat.  42°-o'  N. 

two  blocks  arranged  as  an  L,  and  three  blocks  arranged 
as  a  U. 

As  almost  all  buildings  are  composed,  in  their  elements, 
of  these  simple  shapes,  in  various  combinations,  it  follows 
that  a  careful  study  of  these  diagrams  will  enable  one  to 
criticize  intelligently,  as  far  as  concerns  the  orientation, 
the  plan  of  almost  any  building. 

In  the  single  straight  block  (Fig.  18)  it  will  be  seen  that 
there  is  an  area  of  complete  shadow  present  in  two  of  the 
positions  shown. 

This  area  first  appears  on  September  21  and  increases 
in  size  up  to  December  21,  after  which  it  decreases,  until 
by  March  21  it  has  disappeared  altogether. 


SHADOW   DIAGRAMS 


33 


In  the  other  two  positions  the  absence  of  an  area  of 
complete  shadow  indicates  that  each  wall  of  the  building 
and  all  portions  of  the  ground  around  it  receive  sunlight 
at  some  period  of  the  day  throughout  the  year. 


Fig.  19.  —  Areas  of  complete  shadow;  two  blocks  arranged  as  an  L.  The  solid 
black  represents  the  area  of  complete  shadow  at  the  summer  solstice,  the  lightest 
tint  the  area  of  complete  shadow  at  the  winter  solstice,  and  the  intermediate  tints 
the  areas  of  complete  shadow  at  intervals  one  month  apart  for  the  intervening 
periods  of  the  year.     Lat.  42°-o'  N. 


In  the  case  of  the  L  plan  (Fig.  19)  there  is  one  position 
(that  in  which  the  reentrant  angle  faces  the  north)  in 
which  an  area  of  perpetual  shadow  first  appears,  and 
in   the  U   plan.  (Fig.  20)   there  are  three  such  positions, 


34 


ORIENTATION  OF  BUILDINGS 


Fig.  20.  —  Areas  of  complete  shadow;  three  blocks  arranged  as  a  U. 

The  height  of  the  blocks  in  these  three  diagrams  (Figs.  18,  19  and  20)  is  taken  as 
equal  to  their  width.     Lat.  42°-o'  N. 


SHADOW  DIAGRAMS  35 


those  in  which  the  U  court  faces  north,  northeast,  and 
northwest. 

The  significance  of  these  diagrams  will  perhaps  be  better 
understood  by  a  study  of  Fig.  21,  which  illustrates  the 
method  of  obtaining  the  area  of  complete  shadow  for  the 
L  plan. 

In  all  of  the  foregoing  diagrams  the  height  of  the  blocks 
is  assumed  to  be  equal  to  their  width. 

The  effect  of  an  increase  in  height  will  now  be  con- 
sidered. 

As  the  first  example  we  will  take  the  cube  and  compare 
its  shadow  diagram  with  that  of  a  square  prism  having  a 
height,  let  us  say,  equal  to  five  times  the  width.  We  may 
imagine  the  one  to  represent  a  building  60  feet  square  and 
60  feet  high,  and  the  other  a  tower  60  feet  square  and  300 
feet  high. 

The  diagrams  (Fig.  22)  represent  the  shadow  curves  of 
the  two  at  the  winter  solstice. 

It  will  be  noted  that  the  increase  in  height  enlarges  the 
outer  series  of  curves  but  does  not  affect  those  in  the 
immediate  vicinity  of  the  building,  and,  furthermore,  that 
the  area  of  complete  shadow  is  the  same  in  both  cases. 
An  increase  of  height  of  the  single  straight  block  produces 
a  similar  effect. 

In  certain  positions  of  the  L  and  U  plans,  however,  an 
increase  of  height  produces  an  enlargement  of  the  area 
of  complete  shadow  up  to  a  certain  point,  beyond  which 
any  further  increase  produces  no  further  change  in  the 
area  of  complete  shadow  upon  the  ground. 

It  must  be  remembered,  however,  that  the  presence  of 


36 


ORIENTATION  OF  BUILDINGS 


Fig.  22.  —  Showing  the  effect  of  an  increase  of  height  upon  the  shadow  curves. 
The  lower  diagram  represents  a  cube,  and,  at  a  smaller  scale,  is  identical  with 
Fig.  12.  The  upper  diagram  represents  a  prism  of  a  height  equal  to  five  times 
that  of  the  cube.     Winter  solstice,  Lat.  42°-o'  N.  37 


38 


ORIENTATION  OF  BUILDINGS 


an  area  of  complete  shadow  in  plan  indicates  that  it  also 
extends  over  a  portion  of  the  walls  of  the  building. 

The  maximum  areas  of  complete  shadow  for  the  L  and 
U  plans  produced  by  an  increase  in  height,  are  shown  in 
Fig.  23,  and  in  Fig.  24  is  shown  in  isometric  projection  the 
area  of  complete  shadow  of  the  L  plan,  in  that  position  of 
the  L  in  which  the  reentrant  angle  faces  the  north. 


•s 

s* 

Fig.  23.  —  Showing  the  maximum  areas  of  complete  shadow  for  the  L  and  U 
plans.  The  diagrams  at  the  left  represent  the  winter  solstice;  at  the  right,  the 
summer  solstice,  and  between  the  two,  the  vernal  and  autumnal  equinox.  Lat. 
42°-o'  N. 


It  is  of  course  to  be  understood  that  these  positions  of 
the  L  and  U  plan  are  undesirable. 

For  example,  let  us  imagine  that  we  are  planning  a 
country  dwelling  of  the  farm-house  type.  The  main  por- 
tion of  the  building  has  been  correctly  placed  at  an  angle 
of  450  with  the  meridian  and  the  question  before  us  is 
the  position  of  the  L  or   wing,   containing   the   kitchen 


SHADOW  DIAGRAMS 


39 


Fig.  24.  —  Areas  of  complete  shadow  for  the  L  plan,  autumnal  and  vernal  equi- 
nox, showing  the  effect  of  an  increase  of  height.    Lat.  420  N.      ^ 


40  ORIENTATION  OF  BUILDINGS 

and  shed  (Fig.  25).  Of  the  two  arrangements  shown 
in  the  figure  the  lower  is  to  be  preferred,  since  in  the 
upper  there  is  a  reentrant  angle  facing  the  north,  involv- 
ing an  area  of  complete  shadow  at  all  seasons  of  the 
year. 

The  presence  or  absence  of  an  area  of  complete  shadow 
is  a  useful  criterion  by  which  to  judge  of  the  excellence 
of  any  given  plan,  and  it  is  a  test  which  should 
always  be  applied  in  studying  a  group  of  buildings  or 
in  planning  a  building  having  a  number  of  courts  or 
wings. 

To  determine  the  area  of  complete  shadow  at  the  equi- 
noctial periods  is  a  simple  matter,  since  at  this  time  the 
trace  of  the  sun's  rays  describes  a  plane,  and  the  tips  of 
the  shadows  of  any  object  cast  upon  level  ground  move 
in  a  straight  line  from  west  to  east,  as  we  have  already 
seen  in  the  shadows  of  the  cube. 

As  an  example  let  us  apply  this  test  to  a  type  of  plan 
which  is  quite  a  common  one  for  institutional  buildings 
(Fig.   26). 

It  will  be  found  that,  in  any  position  in  which  this  plan 
may  be  placed,  there  is  an  area  of  complete  shadow  always 
present.1 

In  all  the  cases  so  far  considered,  it  will  be  observed 
that  the  positions  which  give  the  least  amount  of  shaded 
area  are  those  in  which  the  blocks  or  buildings  are  placed 
at  an  angle  of  450  with  the  meridian. 

1  In  making  the  sun  plan  of  a  building  care  must  be  taken  to  distinguish  between 
the  magnetic  north  and  the  true  meridian.  It  is  customary  in  surveyors'  plans 
to  mark  the  magnetic  north  by  the  symbol  of  a  one-sided  arrow,  while  the  true 
north  is  denoted  by  a  full-fledged  arrow. 


SHADOW  DIAGRAMS 


41 


Fig.  25.  —  Good  and  bad  arrangement  of  L.  The  shaded  area  in  the  upper  part 
of  the  figure  shows  the  area  of  complete  shadow  at  the  autumnal  and  vernal  equi- 
nox.   Lat.  42°-o'  N. 


42 


ORIENTATION   OF  BUILDINGS 


The  next  step  in  our  study  will  be  to  consider  the  group- 
ing of  buildings,  such  a  problem,  for  instance,  as  is  presented 
in  planning  a  pavilion  hospital. 

In  studying  groups  of  buildings  we  have  not  only  to  con- 
sider the  shadows  cast  by  the  buildings  upon  the  ground, 


^_H 


Fig.  26.  —  This  is  a  common  type  of  plan  for  hospitals  and  other  institutional 
buildings.  It  is  given  here  as  an  example  to  be  avoided,  since  it  involves  an  area 
of  complete  shadow  in  any  position  in  which  it  may  be  placed. 


but  also  the  shadows  cast  by  the  different  buildings  upon 
each  other.  Figs.  27,  28,  and  29  represent,  in  isometric 
projection,  two  of  our  single  straight  blocks  placed  side 
by  side,  with  the  shadows  as  they  would  be  at  the  winter 
solstice,  when  the  interference  of  one  building  with  another 
is  the  greatest. 


SHADOW   DIAGRAMS  43 


In  Fig.  27  the  long  axis  of  the  blocks  runs  north  and 
south;  in  Fig.  28  east  and  west,  and  in  Fig.  29  northeast 
and  southwest. 

The  latter  figure  will  also  serve  for  the  case  in  which 
the  axis  of  the  blocks  runs  northwest  and  southeast,  the 
forenoon  diagrams  of  the  one  corresponding  to  the  after- 
noon diagrams  of  the  other,  and  vice  versa. 

The  blocks  are  placed  at  a  distance  apart  equal  to  twice 
their  height,  the  arrangement  usually  recommended  for  the 
ward  pavilions  of  a  hospital. 

A  study  of  these  diagrams  which,  as  above  noted,  repre- 
sent the  most  unfavorable  conditions  of  the  whole  year, 
justifies  the  conclusion  that  adequate  sunlight  may  be 
obtained  with  a  distance  between  the  blocks  of  considerably 
less  than  that  shown. 

Such  is  the  kind  of  study  which  the  architect  must 
pursue  in  order  to  become  proficient  in  the  art  of  sun- 
planning. 

How  much  weight  should  be  given  to  the  question  of 
sunlight  must  be  a  matter  for  judgment  in  each  case,  but 
to  wilfully  create  an  area  of  complete  shadow  when,  by  some 
different  arrangement  of  plan,  it  might  have  been  avoided, 
without  detriment  to  more  important  considerations,  can- 
not be  considered  good  architecture. 

Just  as  a  building  should  be  planned  in  all  its  parts 
so  as  to  shed  water,  and  not  invite  the  entrance  of  damp- 
ness into  its  exterior  walls,  so  in  its  general  shape  and 
disposition  it  should  be  planned  so  that  the  sun  may  dry 
out  its  walls  quickly  after  rains,  and  keep  them  clean  and 
bright. 


44 


ORIENTATION  OF  BUILDINGS 


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SHADOW   DIAGRAMS 


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46 


ORIENTATION  OF  BUILDINGS 


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SHADOW   DIAGRAMS 


47 


So  far  we  have  considered  only  the  distribution  of  sun- 
light upon  the  exterior  surfaces  of  buildings  and  upon  the 
ground.  The  admission  of  sunlight  to  the  interior  of  build- 
ings through  windows  will  next  be  considered. 

It  is  evident  that  a  window  facing  the  east,  and  with  an 
unobstructed  outlook,  will  receive  its  maximum  of  sunlight 
at  sunrise  of  the  equinoctial  periods. 

As  the  sun  moves  toward  the  south  and  mounts  higher  and 
higher  in  the  heavens,  his  rays  fall  more  and  more  obliquely 


145' 


Fig.  30.  —  Showing  the  visual  angle  of  an  ordinary  window,  in  a  building  of 
frame  construction. 


through  the  opening,  and  finally  cease  to  come  through  at 
all.  The  angle  at  which  this  will  occur  varies  with  the  width 
and  height  of  the  opening  and  the  depth  of  the  jamb. 

Fig.  30  is  the  plan  of  a  window  of  ordinary  width  in 
a  wall  of  frame  construction.  The  angle  of  1450  shown 
upon  the  diagram  may  be  called  the  visual  angle  of  the 
window. 

If  the  thickness  of  the  wall  is  increased  the  visual  angle 
is  restricted  and  consequently  the  length  of  time  during 
which  the  window  will  admit  sunlight  is  diminished. 


48 


ORIENTATION  OF  BUILDINGS 


By  increasing  the  width  of  the  opening  the  visual  angle 
may  be  enlarged  but  will  always  be  less  than  1800. 


Fig.  31.  —  Chancel  window,  Great  Casterton  Church,  Rutland;  from  An  Analysis 
of  Gothick  Architecture,  by  R.  and  J.  A.  Brandon.     London,  1849. 


The  full  visual  angle  of  1800  can  only  be  obtained  in 
the  oriel  or  bay  window.  We  are  accustomed  to  think  of 
bay  windows  as  having  a  southerly  exposure,  when,  as  a 


SHADOW  DIAGRAMS  49 


matter  of  fact,  their  greatest  usefulness  is  found  when 
they  are  projected  from  the  north  side  of  a  building  to 
catch  the  oblique  rays  of  the  morning  sun,  which  would 
be  shut  out  of  a  window  set  in  the  plane  of  the  wall. 

Bay  windows  are  of  great  use  also  for  city  buildings 
upon  narrow  streets,  where  the  buildings  opposite  shut  out 
the  sunlight  except  when  it  falls  in  an  oblique  direction 
from  either  side. 

The  visual  angle  of  a  window  may  be  increased  by 
beveling  the  jambs,  with  the  advantage  that  the  light  is 
increased  without  any  increase  in  the  glass  surface,  and 
consequent  loss  of  heat  by  radiation. 

The  advantage  of  the  beveled  jamb  was  well  understood 
by  the  mediaeval  builders  (Fig.  31). 


0  10 

i_j 1 1 1 1 — 1 — i— i— i— 1 

FEET 
Fig.  32.  —  Wall  section  of  factory  building  on  Swett  St.,  Boston. 

Fig.  32  illustrates  the  wall  section  of  a  factory  building 
designed  by  the  author,  in  which  the  piers  between  the 
windows  are  reduced  to  a  minimum  width  and  are  also 
beveled,  affording  the  maximum  of  light. 

For  the  following  series  of  window  diagrams  a  window 
has  been  assumed  3  ft.— 6  in.  wide,  and  8  ft.-o  in.  tall, 
with  a  wall  thickness  of  1  ft.-o  in.,  giving  a  visual  angle 


ORIENTATION  OF  BUILDINGS 


of   i48c-6'  and  a  normal   area  of  opening  of   28  square 
feet. 

The  diagrams  (Figs.  33  to  35)  represent  the  plan  of  a 
room  24  feet  square,  lighted  by  a  single  window  of  the 
dimensions  given  and  with  the  window  sill  at  a  height 
of  2  feet  above  the  floor. 


*  v\  V.    1/   '''  ' 


\\  \    \ 


Fig.  11.  —  Showing  the  area  of  floor  subject  to  direct  sunlight,  for  windows  of 
different  aspects;  winter  solstice;  Lat.  42°-o'  N. 


SHADOW  DIAGRAMS 


51 


The  parallelograms  in  dotted  lines,  somewhat  resembling 
a  deformed  pack  of  cards  spread  upon  the  floor,  indicate 
the  areas  in  sunlight  at  successive  hours,  and  the  curved 
figures  resulting  therefrom   the  whole  area  subjected   to 


iiiiiiinniin 


IjTlTffm^iiiii^HtnilTill 

Fig.  34.  —  Showing  the  area  of  floor  subject  to  direct  sunlight,  for  windows  of 
different  aspects;  autumnal  and  vernal  equinox;  Lat.  42°-o'  N. 


52 


ORIENTATION  OF  BUILDINGS 


sunlight,    for   the  various   exposures   and   at   the  various 
seasons  indicated. 

If  the  room  of  our  diagram  were  carpeted  with  a 
dark  material  having  the  property  of  becoming  instantly 
bleached  by  exposure  to  direct  sunlight,  it  would  present 


+^-■""""'.--'1     bfl 

*/     y      ..,,,'■  i ' 

1 

\ 

Fig.  35.  —  Showing  the  area  of  floor  subject  to  direct  sunlight,  for  windows  of 
different  aspects;  summer  solstice;  Lat.  42°-o'  N. 


SHADOW  DIAGRAMS 


53 


an  appearance  at  the  end  of   the  day  corresponding  to 
these  diagrams. 

The  rays  of  sunlight  passing  through  any  aperture,  as 
a  window,  form  a  prism,  the  cross  section  of  which  changes 
as  the  angle  of  sunlight  changes.  The  area  of  such  a 
cross  section  is  the  normal  area  of  the  aperture  for  the 
admission  of  sunlight  at  the  particular  instant  at  which 
it  is  taken.  The  cross  section  of  such  a  prism  may  be 
found  by  descriptive  geometry. 


vi    vii  viir    ix     x     xi 

Fig.  36.  —  The  parallelograms  in  the  lower  part  represent  the  cross  sections 
of  the  sunlight  prism  of  an  east  window,  for  the  hours  indicated,  at  the  autumnal 
and  vernal  equinox.  The  figure  in  the  upper  part  is  a  graphic  representation  of 
the  total  quantity  of  sunlight  admitted  by  the  window,  and  is  identical  with  the 
corresponding  one  of  Fig.  38,  but  at  a  larger  scale.  Dimensions  of  window: 
3  ft.— 6  in.  wide,  8  ft.-o  in.  tall,  and  1  ft.-o  in.  wall  thickness. 


The  parallelograms  in  the  above  diagram  (Fig.  36)  rep- 
resent the  cross  sections  of  the  sunlight  prism  of  an  east 
window  of  the  dimensions  assumed,  taken  at  intervals  of 
one  hour,  at  the  period  of  the  equinoxes. 


54  ORIENTATION  OF  BUILDINGS 

The  areas  of  these  sections  are  as  follows: 

a.m.  Square  Feet. 

6       28.00 

7       25.05 

8       20.39 

9       14-50 

10      7-86 

11       1-35 

11. 17      o. 

These  areas  may  be  represented  by  lines  of  varying  length 
and  are  so  represented  by  the  vertical  lines  above  them. 

Joining  the  extremities  of  these  lines  by  a  curve,  we 
obtain  a  figure  the  height  of  which  at  any  point  will  repre- 
sent the  area  of  the  sunlight  prism  at  the  corresponding 
hour,  and  the  area  of  the  whole  figure  the  total  amount 
or  quantity  of  sunlight  admitted  by  the  window  during 
the  day. 

It  is  in  this  manner  that  the  figures  of  the  succeeding 
diagrams  (Figs.  37,  38,  and  39)  have  been  drawn.1 

In  order  to  compare  these  areas  we  will  take  as  a  unit 
the  quantity  of  sunlight  which  passes  through  an  opening 
one  foot  square,  in  a  plane  normal  to  the  sun's  rays,  in 
one  hour. 

The  areas  of  the  figures  may  then  be  expressed  in  terms 
of  this  unit,  which  for  convenience  we  will  call  a  sun  hour, 
as  in  Table  II. 

The  heating  effect  of  the  sun  hour  will,  of  course, 
vary  with  the  altitude  of  the  sun  and  atmospheric  condi- 

1  Each  division  of  the  vertical  scale  in  these  figures  corresponds  to  ten  square 
feet. 


N 

N 

E 

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V    VI  VII  VIII  IX   X    XI  XII    I     II    III   IV   V    VI  VII 

Fig.  37.  —  Showing  the  quantity  and  duration  of  direct  sunlight  admitted  by 
windows  of  different  exposures;  winter  solstice;  Lat.  42°-o'  N.  Note  the  large 
amount  admitted  by  the  south  window.  For  the  areas  of  these  figures  see  Table 
II,  page  58.  SS 


Fig.  38.  —  Showing  the  quantity  and  duration  of  direct  sunlight  admitted  by 
windows  of  different  exposures;  autumnal  and  vernal  equinox,  Lat.  42°-o'  N. 
Note  that  the  amount  admitted  by  the  south  window  is  much  less  than  in  the 
preceding  diagram.     For  the  areas  of  these  figures  see  Table  II,  page  58.  56 


Fig.  39.  —  Showing  the  quantity  and  duration  of  direct  sunlight  admitted  by- 
windows  of  different  exposures;  summer  solstice;  Lat.  42°-o'  N.  Note  the  small 
amount  admitted  by  the  south  window.  For  the  areas  of  these  figures  see 
Table  II,  page  58.  57 


58 


ORIENTATION  OF  BUILDINGS 


tions.     However,  an  approximate  value  may  be  assigned 

to  it. 

TABLE   II 

TABLE  OF  WINDOW  VALUES  EXPRESSED  IN   "  SUN  HOURS  " 


:> 

Winter 
Solstice. 

Equinoxes. 

Summer 
Solstice. 

North 

Northeast  and  northwest 

East  and  west 

Southeast  and  southwest 

32.9 
108.5 

152.9 

18.6 
82.7 

IOS-5 
81. 1 

6.8 

73-2 

no.  7 

53-4 
16.  2 

South 

An  average  of  twelve  observations  taken  at  the  Astro- 
physical  Observatory  in  Washington  in  1902-3,  under  the 
direction  of  Mr.  C.  G.  Abbot,1  gives  the  intensity  of  the 
solar  rays  at  the  earth's  surface  in  the  afternoon,  as  1.24 
small  calories  per  square  centimeter  per  minute.  Trans- 
posing this  value,  we  obtain  for  the  energy  contained  in  a 
prism  of  the  sun's  rays  one  foot  square  in  section  shining 
for  one  hour  (the  sun  hour  of  our  diagrams),  the  equiva- 
lent of  274  British  thermal  units;  an  amount  of  energy, 
which,  if  it  could  be  entirely  converted  into  heat  would 
be  sufficient  to  raise  one  gallon  of  water  330  F.,  or  150 
cubic  feet  of  air  ioo°  F.  in  temperature. 

The  determination  of  the  solar  constant,  or  the  intensity 
of  the  solar  rays  in  space,  at  the  mean  distance  of  the 
earth,  is  one  of  the  most  difficult  problems  in  physical 
science,  since  the  amount  of  heat  absorbed  by  the  earth's 
atmosphere  cannot  be  directly  measured,  but  must  be  cal- 
culated theoretically. 

It  may  well  be  that  the  term  solar  constant  is  in  it- 
self an  unwarranted  assumption  and  one  that  has  tended 

1  Smithsonian  Miscellaneous  Collections,  Volume  XLV. 


SHADOW   DIAGRAMS 


59 


to  mislead  the  experimenter,  since  recent  investigations 
appear  to  show  that  the  heat  emitted  from  the  sun  is  not 
steadily  uniform  but  fluctuates  in  some  degree,  in  a  man- 
ner not  yet  satisfactorily  accounted  for. 

The  foregoing  diagrams  are  calculated  for  windows  with 
unobstructed  outlook.  The  effect  of  an  obstruction  will 
now  be  considered. 


Fig.  40.  —  Showing  the  obstructed  horizon  of  city  buildings.     No  sunlight  can 
come  into  the  window  until  the  plane  of  the  sun's  rays  has  reached  the  altitude  AP. 


As  an  example  of  obstructed  outlook,  frequent  in  cities 
and  towns,  we  shall  take  the  case  of  a  lower-story  window 
facing  a  row  of  buildings  60  feet  away.  We  shall  assume 
the  cornice  line  of  these  buildings  to  be  40  feet  above  the 
ground  and  to  extend  indefinitely  in  both  directions  from 
the  point  opposite  our  window. 

The  assumed  conditions  are  shown  in  Fig.  40. 


60  ORIENTATION  OF  BUILDINGS 

It  is  clear  that  no  sunlight  can  come  into  the  window 
until  the  plane  of  the  sun's  rays  has  reached  the  altitude 
AP,  but  that  after  the  altitude  BP  has  been  reached  the 
obstruction  will  have  no  further  effect. 

The  hour  angles  corresponding  to  these  altitudes  may 
be  calculated. 

Let  it  be  required  to  find  the  time  at  which  the  sunlight 
will  first  come  into  a  window  with  an  east  exposure,  under 
the  conditions  assumed  in  the  diagram,  and  at  the  period 
of  the  winter  solstice. 

The  angular  altitude  of  the  obstruction  above  the  top 
of  the  window  {i.e.  the  slope  of  the  line  AP)  is  found  by 
measurement  to  be  22°-37'  and  the  problem  consists  in 
determining  the  hour  angle  at  which  the  plane  of  the  sun's 
rays  will  reach  this  elevation. 

For  the  purpose  of  representing  the  problem  it  will  be 
convenient  to  use  the  stereographic  projection  (Fig.  41). 
The  enclosing  circle  is  the  horizon;  NS  the  meridian;  P  the 
celestial  north  pole;  the  dotted  circle  the  path  of  the  sun 
at  the  winter  solstice,  and  NXS  a  great  circle  of  the  sphere 
formed  by  a  plane  intersecting  the  plane  of  the  horizon  on 
the  north  and  south  line  and  making  an  angle  of  22°-^' 
with  it. 

The  intersection  of  this  circle  with  the  dotted  circle  (at 
the  point  X)  determines  the  position  of  the  sun  required, 
and  the  calculation  of  the  spherical  triangle  SPX  gives 
us  the  hour  angle  (at  P)  which  we  find  to  be  /\o°-/[Y ,  corre- 
sponding to  9  I1.-17  m.  a.m.  solar  time. 

Similarly  the  hour  angle  corresponding  to  the  elevation 
BP  is  found  to  be  35°-32'  or  9  I1.-38  m.  solar  time.     In 


SHADOW   DIAGRAMS 


61 


other  words,  the  effect  of  the  obstruction  is  to  cut  off  all 
sunlight  from  this  window  until  9  h.-i7  m.  a.m.  and  a 
portion  of  the  sunlight  from  9  I1.-17  m.  to  9  I1.-38  m., 
after  which  the  obstruction  ceases  to  have  any  further 
effect. 


Fig.  41.  —  Use  of  the  stereographic  projection  to  represent  the  conditions 

shown  in  Fig.  40. 


In  the  case  of  the  southeast  window  the  obstruction  is 
complete  until  10  I1.-27  m.  and  partial  until  11  h.-20  m. 

In  the  case  of  the  south  window  the  obstruction  is  com- 
plete before  10  h-24  m.  a.m.  and  after  1  h-36  m.  p.m., 
between  which  hours  the  obstruction  is  partial. 


62 


ORIENTATION   OF  BUILDINGS 


For   the  southwest  and   the  west  windows  the  effects 
correspond  to  those  for  the  southeast  and  east  windows. 
The  results  are  shown  in  diagrammatic  form  in  Fig.  42. 


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^"v.^ 

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Ifesw 

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"■S. 

" 

E 

/m 

\^ 

--+-. 

^' 

.-•^ 

s 

1 

-^-^ 

■~-^_ 

r" 
1 

1 

-I 
1 
1 

1 

^^ 



--> 

1 

s 

'^ 

1 
1 
1 

! 

1 

1 

y^ 

V 

/ 

^ 

**    j 

^m 

\ 

V 

[IV. 

[II I 

X    ) 

Li 

I  X 

II 

II    III    I 

1 

V    A 

T 

Fig.  42.  —  Showing  the  quantity  and  duration  of  direct  sunlight  admitted  by 
a  window  with  obstructed  outlook,  under  the  conditions  shown  in  Fig.  40,  for 
different  exposures;  winter  solstice;  Lat.  42°-o'  N.  The  full  areas  of  the  figures 
are  identical  with  those  of  Fig.  37;  the  shaded  portions  show  the  quantity  of  sun- 
light admitted  by  the  obstructed  window. 

It  may  be  noted  from  these  window  diagrams  that  the 
unobstructed  south  window  in  winter   admits  more  sun- 


SHADOW  DIAGRAMS  63 


light  than  any  of  the  other  exposures,  at  any  period  of 
the  year,  while  the  same  window  in  summer  admits  less 
than  any  of  the  other  exposures,  except  the  north.  The 
effect  of  obstruction,  however,  is  serious  upon  the  south 
window  in  winter,  when  sunlight  is  most  to  be  desired. 

The  southeast  and  southwest  windows  partake  to  some 
degree  of  the  character  of  the  south  window,  in  that  they 
show  a  maximum  in  winter  and  a  minimum  in  summer, 
although  the  variation  is  not  as  great  as  in  the  south 
window. 

The  east  and  west  windows  on  the  contrary  show  a 
maximum  in  summer  and  a  minimum  in  winter,  and  are 
consequently  less  desirable  exposures  than  the  south,  south- 
east, or  southwest. 

The  results  thus  theoretically  obtained  may  be  confirmed 
in  a  striking  manner  with  a  sun  box. 

A  sun  box  is  essentially  a  box  or  chamber  of  non-heat- 
conducting  material,  having  on  one  side  a  window  or  light 
of  glass,  sealed  tight  to  prevent  air  leakage. 

Such  a  box,  when  the  window  is  turned  toward  the 
sun,  will  accumulate  heat  much  faster  than  it  is  lost  by 
radiation. 

Fig.  43  illustrates  the  construction  of  the  sun  boxes 
employed  by  the  author  in  experiments  at  Boxford,  Mas- 
sachusetts (Lat.  42°-4o'  N.). 

Two  of  these  boxes  were  made,  as  nearly  alike  as 
possible. 

They  were  constructed  of  ordinary  pine  boards  §  inch 
thick,  nailed  together,  without  grooving  or  dovetailing. 

The    inner    box    (1    foot    square,    inside    measurement) 


64 


ORIENTATION   OF  BUILDINGS 


was  covered  with  one  thickness  of  lino-felt  (a  non-heat- 
conducting  material  made  of  flax  fiber  quilted  between 
two  thicknesses  of  building  paper). 


Fig.  43.  —  Cross-section   of   sun   box.      A.  Hood   or   cover.      B.  Outer   box. 
C.  Air  space.     D.  Lino-felt.     E.  Inner  box.     T.  Thermometer.     S.  Shield. 


The  sash  (glazed  with  |-inch  plate  glass)  was  screwed 
into  place  and  fitted  tightly  against  a  felt  weather  strip 
all  around  the  edges. 

The  boxes  were  painted  on  the  outside  one  coat  of  white 
paint  and  were  shielded  from  the  sun's  direct  rays,  except 
on  the  window  side,  by  wooden  hoods  or  covers. 


SHADOW   DIAGRAMS 


65 


The  temperature  of  the  air  inside  the  boxes  was  shown 
by  a  thermometer  on  the  rear  wall,  in  front  of  which  was 
placed  a  wooden  screen,  sufficiently  tall  to  shield  the  bulb 
from  the  sun's  direct  rays,  while  permitting  the  scale  to 
be  read  from  the  outside.1 


Fig.  44.  —  View  of  sun  boxes. 

The  boxes  were  exposed  to  the  sun  on  a  platform  about 
three  feet  above  the  ground,  in  an  open  field,  with  free 
access  of  sunlight  from  every  quarter  (Fig.  44).  The 
platform  was  marked  with  a  system  of  lines  running  north 
and   south,    and   east   and   west,    with   diagonals   in   both 

1  The  protecting  covers  and  thermometer  shields  were  omitted  in  the  first 
few  experiments. 


66  ORIENTATION  OF  BUILDINGS 

directions,  so  that  it  was  a  simple  matter  to  set  the  boxes 
facing  in  any  direction  desired. 

In  the  earlier  experiments  the  boxes  were  unsealed  at 
the  close  of  each  day  and  allowed  to  remain  until  the 
temperatures  were  the  same  in  each,  when  they  were  again 
sealed  up  and  set  for  the  next  experiment.  In  the  later 
experiments  this  was  not  done,  as  it  was  found  that  the 
temperatures  became  equalized  by  radiation  during  the 
night. 

Notwithstanding  the  fact  that  the  boxes  were  of  the 
same  shape,  size,  and  construction,  it  was  found  that  there 
was  a  difference  between  them,  as  shown  by  the  experi- 
ments of  July  14  and  15,  in  which  both  boxes  were  set  for 
the  same  exposure  and  yet  showed  a  difference  of  several 
degrees  in  temperature  under  apparently  the  same  con- 
ditions. 

For  this  reason  the  experiments  do  not  afford  an  absolute 
basis  of  comparison  between  different  exposures,  such  as 
might  be  obtained  with  apparatus  more  carefully  made 
and  experiments  more  carefully  conducted. 

By  comparing  the  records  for  the  same  box,  however, 
the  relative  efficiency  of  the  same  exposure  at  different 
periods  of  the  year  is  shown  with  sufficient  exactness,  and 
follows  quite  closely  the  theoretical  conclusions  deduced 
from  the  diagrams. 


SUN    BOX    RECORDS 


The  following  is  a  record  of  experiments  made  with  these  boxes  during 
the  season  of  iqio.  All  of  them  (except  as  noted)  were  made  on  clear, 
bright  days,  with  few  or  no  clouds.  All  temperatures  are  in  degrees 
Fahrenheit  and  all  hours  in  solar  time. 


67 


68 


ORIENTATION   OF  BUILDINGS 


JUNE  26 


Time. 

Air. 

Box  A,  East. 

BoxB,  South. 

A.M. 

I  1 

5-48 

63 

72 

54 

2 

6.36 

66 

80 

57 

3 

7.08 

74 

IOO 

62 

4 

8. 

73 

124 

68 

5     . 

9-38 

P.M. 

So 

122 

-85 

6 

12.33 

85 

I05 

no 

7 

i-33 

85 

I05 

112 

8 

2.23 

85 

I03 

108 

9 

3-53 

85 

IOO 

104 

10 

6.58 

72 

85 

85 

11 

7.18 

70 

83 

83 

Remarks.  —  No  hoods  on  boxes.     No  shield  for  thermometers  in  boxes. 

1.  Both  boxes  wet  with  dew.  Glass  wet  on  B.  Sun  partially  obscured 
by  haze.  Later  on  the  haze  wore  off  and  it  was  a  fine  day,  with  flying 
clouds. 


JUNE  29 


Time. 

Air. 

Box  A ,  East. 

Box  B,  Southeast. 

A.M. 

I 

5.28 

62 

90 

54 

2 

6.20 

69 

114 

67 

3 

7-33 

71 

138 

92 

4 

8.28 

71 

137 

97 

5 

9.28 

72 

123 

114 

6 

10.28 

75 

117 

117 

7 

11.28 

P.M. 

76 

107 

114 

8 

1 -13 

77 

IOO 

103 

9 

3-i3 

77 

93 

95 

10 

4-43 

77 

•    90 

9i 

n 

6.28 

78 

85 

86 

12 

9-13 

52 

66 

65 

Remarks.  —  No  hoods  on  boxes. 
Remarkably  clear  day. 

1.  Glass  of  B  covered  with  dew. 

2.  Dew  has  disappeared. 
5.   Glass  on  A  misty. 

7.   Glass  on  A  clear. 


No  shields  for  thermometers  in  boxes. 


SHADOW  DIAGRAMS 


69 


JUNE  30 


Time. 

Air. 

Box  A ,  West. 

Box  B,  South. 

A.M. 

I 

7-7 

78 

62 

64 

2 

9.17 

82 

78 

88 

3 

10.42 

82 

88 

102 

4 

11.42 

P.M. 

84 

94 

no 

5 

I.  12 

84 

102 

112 

6 

2.  17 

86 

118 

no 

7 

3-i7 

84 

138 

IOzl 

8 

4.27 

84 

144 

100 

9 

5-27 

80 

98 

10 

6.27 

72 

112 

88 

11 

6-57 

67 

102 

85 

Remarks.  —  No  hoods  on  boxes.     No  shields  for  thermometers  in  boxes. 

8.  The  temperature  of  1440  recorded  in  Box  A  is  the  highest  which  the 
thermometer  registers. 

9.  Glass  in  A  misty  so  that  thermometer  cannot  be  seen. 


JULY  s 


Time. 

Air. 

Box  A ,  South. 

Box  B,  Northeast. 

A.M. 

I 

6.06 

72 

47 

80 

2 

7.06 

72 

54 

98 

3 

8. 11 

80 

70 

108 

4 

9. 11 

84 

82 

no 

5 

10. 11 

84 

99 

108 

6 

11. 41 

B.M. 

84 

no 

106 

7 

12.41 

86 

116 

106 

8 

1. 41 

87 

117 

104 

9 

2.26 

88     ■ 

116 

102 

10 

4. II 

86 

106 

100 

n 

5-H 

86 

102 

96 

12 

7-5i 

64 

84 

82 

Remarks.  —  No  hoods  on  boxes.     Clear  day. 
1.   Glass  of  A  covered  with  dew. 


7° 


ORIENTATION  OF  BUILDINGS 


JULY  7 


Time. 

Air. 

Box  A ,  South. 

Box  B,  East. 

A.M. 

I 

6. ii 

55 

48 

85 

2 

7.00 

63 

55 

108 

3 

7-31 

68 

60 

115 

4 

9-36 

82 

84 

132 

5 

10.41 

86 

96 

122 

6 

11. 41 

P.M. 

86 

106 

112 

7 

12.41 

88 

112 

I06 

8 

I  .  26 

90 

112 

I02 

9 

3.0I 

88 

108 

98 

IO 

3-51 

84 

100 

94 

ii 

4.46 

98 

98 

96 

12 

5-41 

92 

94 

92 

Remarks.  —  No  hoods  on  boxes.     Perfectly  clear  day. 

11.  Air  thermometer  in  direct  sunlight.., 

12.  Air  thermometer  in  direct  sunlight. 


JULY   ro 


Time. 

Air. 

Box  A ,  South. 

Box  B,  East. 

A.M. 

I 

5-36 

62 

62 

68 

2 

7-5i 

80 

72 

no 

3 

8.26 

84 

77 

117 

4 

9.26 

91 

87 

124 

5 

10. 26 

96 

99 

124 

6 

11 .41 

P.M. 

IOO 

no 

118 

7 

12.41 

102 

116 

114 

8 

I  .06 

IOO 

117 

112 

9 

i-5i 

IOO 

118 

109 

10 

2.41 

95 

114 

106 

11 

3-4i 

94 

no 

104 

12 

4-51 

91 

i°5 

IOO 

Remarks:  — 
1.   Slight  haze:  humidity  high. 

7.  Floating  clouds. 

8.  Floating  clouds. 

9.  Thunder  clouds. 
12.    Clear:  good  breeze. 


SHADOW  DIAGRAMS 


71 


JULY   14 


Time. 

Air. 

Box  A ,  East. 

Box  B,  East. 

A.M. 

I 

6. 10 

61 

98 

100 

2 

6.50 

71 

118 

121 

3 

7.40 

74 

126 

131 

4 

8.10 

78 

132 

136 

5 

g.io 

80 

136 

138 

6 

10.10 

88 

138 

138 

Remarks.  —  Clear   day.     Boxes  placed  side  by  side,   B  being  to  the 
north  of  A . 

JULY   15 


Time. 

Air. 

Box  A ,  East. 

Box  B,  East. 

A.M. 

6-55 

68 

102 

I02 

7-35 

70 

"5 

117 

8.10 

76 

124 

126 

0. 10 

80 

132 

130 

10. 10 

82 

128 

128 

Remarks.  —  Somewhat   cloudy   in   early   morning 
placed  side  by  side,  A  being  to  the  north  of  B. 


clear   later.     Boxes 


JULY  20 


Time. 

Air. 

Box  A,  East. 

Box  B,  Southeast. 

A.M. 

5- 

5° 

60 

52 

6.40 

59 

105 

76 

7- °5 

62 

114 

84 

7-35 

65 

120 

94 

7-55 

68 

126 

102 

8.25 

70 

122 

IO4 

8. 55 

76 

Il8 

I06 

9-25 

76 

Il8 

I08 

9-55 

78 

I20 

no 

10.25 

78 

no 

112 

11 .  10 

76 

106 

no 

n-55 

78 

I02 

108 

P.M. 

12.25 

78 

96 

100 

2.25 

78 

86 

86 

3-55 

78 

82 

82 

Remarks.  —  Clear  day. 


72 


ORIENTATION   OF  BUILDINGS 


JULY  21 


Time. 

Air. 

Box  A ,  Southeast. 

Bos  B,  East. 

A.M. 

I 

5- 

56 

54 

56 

2       ) 

6.40 

64 

74 

96 

3 

7-05 

66 

82 

105 

4 

7-35 

68 

91 

116 

5 

8. 

72 

98 

129 

6 

9- 

76 

no 

128 

7 

10.45 

86 

120 

118 

8 

11.45 

P.M. 

90 

118 

112 

9 

12-35 

94 

112 

108 

IO 

2-15 

90 

102 

102 

ii 

3-3° 

86 

98 

98 

12 

5.20 

80 

90 

90 

Remarks: 

1.   Sun  rising  through  cloud  bank. 
3.   Perfectly  clear. 


JULY  24 


Time. 

Air. 

Box  A,  Southwest. 

Box  B,  Southeast. 

A.M. 

8.04 

78 

67 

86 

8.44 

84 

72 

98 

9-34 

88 

78 

108 

10. 19 

9° 

85 

116 

10.54 

94 

92 

118 

n-54 

99 

104 

120 

P.M. 

i-39 

98 

III 

112 

2.49 

96 

114 

107 

4-39 

94 

122 

102 

5- 

94 

121 

IOI 

5-24 

92 

116 

100 

Remarks.  —  Somewhat  cloudy  day. 


SHADOW  DIAGRAMS 


73 


AUGUST  7 


Time. 

Air. 

Box  A ,  South, 

BoxjB,  East. 

A.M. 

I 

7-45 

68 

61 

121 

2 

8-35 

72 

68 

I30 

3 

9- 

71 

73 

I30 

4 

9-35 

P.M. 

76 

81 

129 

5 

12.  IO 

8l 

105 

108 

6 

i-45 

■          83 

104 

102 

7 

4.40 

77 

96 

90 

8 

6-35 

68 

84 

80 

Remarks: 

3.    Sun  behind  thin  clouds. 

6.    Sun  behind  clouds. 


AUGUST  21 


Time. 

Air. 

Box  A ,  West. 

Box  B ,  Southeast. 

A.M. 

8.28 

72 

56 

104 

9-!3 

75 

60 

114 

10.13 

80 

67 

123 

11.08 

80 

72 

125 

P.M. 

1 -13 

81 

88 

no 

1-53 

79 

97 

104 

2.08 

76 

118 

94 

3-33 

76 

123 

9i 

4-i3 

76 

132 

6.48 

67 

103 

76 

Remarks.  —  Clear  day. 


74 


ORIENTATION   OF  BUILDINGS 


AUGUST   28 


Time. 

Air. 

Box  A ,  South. 

Box  B ,  Southeast. 

A.M. 

I  ■> 

7 

14 

65 

46 

76 

2 

8 

29 

7° 

61 

102 

3 

8 

59 

72 

68 

no 

4 

9 

29 

74 

77 

116 

5     - 

11 

14 

78 

114 

123 

6 

11 

50 

78 

112 

119 

P.M. 

7 

12  .  20 

80 

117 

118 

8 

12  .40 

80 

117 

114 

9 

i-5° 

82 

120 

107 

10 

2.30 

S3 

11S 

103 

11 

5- 

70 

95 

86 

12 

7-14 

63 

75 

72 

Remarks: 

6.  Slightly  cloudy. 

7.  Clear  again. 

8.  Slightly  cloudy. 

9.  Slightly  cloudy. 
10.    Clear. 


SEPTEMBER  18 


Time. 

Air. 

Box  A ,  South. 

Box  B,  East. 

A.M. 

6.31 

47 

44 

57 

7.40 

60 

5i 

97 

8.46 

68 

68 

112 

9. II 

69 

75 

114 

936 

72 

85 

114 

IO.51 

76 

104 

106 

II .  26 

77 

113 

102 

P.M. 

12.51 

82 

127 

95 

2.  l6 

81 

127 

93 

3.06 

82 

122 

92 

4.l6 

80 

no 

89 

5.06 

76 

100 

85 

7.l6 

70 

82 

76 

Remarks.  —  Clear  day. 


SHADOW  DIAGRAMS 


75 


OCTOBER  24 

Time. 

Air. 

Box  A ,  South. 

Box  B,  East. 

A.M. 

6.19 

32 

32 

32 

7- 

36 

33 

45 

7-46 

39 

42 

70 

8. 11 

4i 

50 

80 

8.31 

42 

58 

87 

9.04 

44 

70 

92 

9-31 

45 

79 

93 

10.46 

5° 

IOI 

85 

11. 51 

52 

116 

74 

P.M. 

12.  II 

55 

119 

72 

I. II 

57 

123 

68 

1-33 

58 

125 

67 

i-5S 

59 

125 

67 

2. 11 

59 

124 

66 

3-03 

58 

107 

64 

4.41 

53 

84 

60 

6.31 

46 

63 

52 

Remarks.  —  Remarkably  clear  day. 

DECEMBER  22 


Time. 

Air. 

Box  A ,  South. 

Box  B,  East. 

A.M. 

I 

9-47 

16 

56 

45 

2 

10.57 

P.M. 

20 

88 

46 

3 

12.52 

24 

114 

38 

4 

I  .42 

25 

"5 

44 

5 

3.22 

24 

94 

33 

Remarks.  —  Clear  day. . 

4.   The  reading  in  Box  B  is  probably  an  error. 


76 


ORIENTATION  OF  BUILDINGS 


6789       10      11      12       123456 


100 


JUL.  7 


100 


^-— 

~"">><C___ 

vf 

_L^ 



--^" 

,""  ^ 

•ZZ~- 

~~  8 

SEP.  18 


100 


x^ 

[ 

y 

_____ 

■^-K 

_^- 

U=— 

*= — 

— 

-^-- 

OCT.  24 


100 


/- 

■  / 

y 

_l 

— 

— -- 

"" ' 

DEC.  22 

Fig.  45.  —  Sun-box  records  for  south  and  east  exposures.  The  dotted  lines 
show  the  temperature  of  the  air;  the  full  lines  the  temperatures  within  the  boxes. 
The  figures  at  the  top  denote  the  hours  of  the  day.  The  divisions  of  the  vertical 
scale  are  equal  to  ten  degrees  of  temperature. 


SHADOW   DIAGRAMS 


77 


The  records  of  July  7,  September  18,  October  24,  and 
December  22  are  shown  graphically  in  Fig.  45  the  tempera- 
ture being  plotted  in  the  form  of  curves;  the  dotted  curve 
showing  the  temperature  of  the  air  outside  and  the  solid 
curves  that  of  the  air  within  the  boxes. 


Fig.  46.  —  Mr.  Cabot's  sun  house. 


Each  horizontal  division  of  the  scale  corresponds  to  one 
hour  of  time  and  each  vertical  division  to  io°  of  tem- 
perature. 

The  boxes  occupied  the  same  relative  position  in  all 
four  experiments,  so  that  the  records  show  very  well  the 
change  in  efficiency  of  the  same  exposure  with  the  change 
of  seasons. 


78  ORIENTATION   OF   BUILDINGS 

That  the  sun's  rays  are  not  of  indifferent  value  in  the 
heating  of  our  houses  in  winter  is  shown  by  the  last  ex- 
periment (December  22),  in  which  the  air  within  the  sun 
box  reached  a  temperature  of  1150  F.  with  the  air  outside 
at  250  F. 

Every  dwelling  may  be  converted  into  a  sun  box  by 
properly  insulating  the  outside  walls.  Fig.  46  is  reproduced 
from  a  photograph  of  a  "sun  house"  built  by  the  late  Mr. 
Samuel  Cabot,  on  his  place  at  Canton,  Massachusetts. 
This  little  building  faces  the  south,  on  a  southerly  slope, 
and  is  quite  shallow  in  proportion  to  its  breadth. 

The  walls  and  roof  are  thoroughly  insulated. 

A  temperature  of  ioo°  F.  and  over  has  been  frequently 
attained  within  this  building  with  an  outside  temperature 
of  zero  or  lower,  entirely  from  the  warmth  of  the  sun's 
rays. 

The  foregoing  study  of  windows  has  an  important  bear- 
ing on  the  orientation  of  hospital  buildings,  and  in  the  next 
chapter  we  shall  take  up  the  question  of  hospitals  in  some 
detail. 


CHAPTER  III 
Hospitals 

The  typical  hospital  ward  is  a  long,  narrow  room,  with 
windows  on  both  sides,  between  the  beds.  In  the  open- 
ended  type  of  ward  there  are  windows  also  at  one  end, 
and  these  are  of  great  value,  especially  in  winter,  as  will 
presently  be  shown. 

A  typical  ward  pavilion  of  the  open-ended  type  is  shown 
in  Fig.  47. 

There  is  a  difference  of  opinion  as  to  the  best  orientation 
for  ward  pavilions. 

In  a  description  of  the  Heidelberg  University  Hospital, 
given  in  Mouatt  &  Snell's  Hospital  Construction  and  Man- 
agement, it  is  stated  that  "The  question  of  the  aspect 
of  the  windows  of  the  wards  was  only  settled  after  very 
great  deliberation  by  the  authorities  charged  with  the 
erection  of  this  building,  and  Dr.  Knauff  gives  in  his  work l 
a  very  exhaustive  account  of  the  considerations  ^which 
ultimately  led  to  the  determination  of  the  placing  of  the 
axes  of  the  various  pavilions  as  nearly  east  and  west  as 
the  shape  of  the  ground  would  permit.  Actually  their 
direction  is  about  E.  S.  E.  and  W.  N.  W.  It  is  remarkable 
that  the  Friedrichshain  building  authorities,  as  the  result 
of  their  deliberations  on  this  question,  arrived  at  an  exactly 
opposite  conclusion,  and  placed  the  axes  of  their  pavilions 
directly  north  and  south." 

1  Das  Neue  Academische  Krankenhaus  in  Heidelberg,  Munchen,  1879. 

79 


8o 


ORIENTATION  OF  BUILDINGS 


Fig.  47.  —  Typical  one  story  ward  pavilion  of  twenty-four  beds.  This  plan  is  not 
given  as  an  example  to  be  followed,  but  to  illustrate  several  common  faults. 
The  orientation  is  bad,  giving  the  minimum  of  sunlight  in  winter  and  the  max- 
imum in  summer.  The  arrangement  of  the  windows,  one  for  each  two  beds,  is  not 
as  good  as  one  for  each  bed.  The  ward  itself  has  excessive  length  in  proportion 
to  its  width,  giving  an  unpleasing  effect  to  the  interior,  and  the  distance  to  be 
traversed  by  the  nurses,  in  going  to  and  from  the  service  rooms,  is  excessive. 

A  good  feature  of  the  plan  is  the  large  bay  window  at  the  south  end;  if  it  were 
not  for  this  the  ward  would  have  very  little  sunlight  in  winter.  The  building 
would  be  improved  by  making  the  service  portion  (shaded),  two  stories  in  height, 
after  the  manner  of  the  Virchow  ward  unit.     (See  Fig.  56.) 


HOSPITALS 


In  the  Handbook  for  Hospitals  [No.  32  of  the  pub- 
lications of  the  State  Charities  Aid  Association  of  New 
York  (N.Y.,  1883)],  it  is  recommended  that  the  long  axes 
of  the  wards  should  run  as  nearly  as  possible  from  north- 
east to  southwest. 

The  majority  of  those,  however,  who  have  written  on 
hospital  construction  incline  to  a  north  and  south  direc- 
tion. 

This  is  the  orientation  recommended  by  Sir  Douglas 
Gal  ton  (Healthy  Hospitals,  Oxford,  1893): 

"The  arrangement  by  which  sunshine  will  always  fall 
to  the  largest  extent  on  the  space  between  pavilions,  and 
also  be  distributed  most  evenly  upon  the  wall  surface,  is 
obtained  in  this  country  (England)  by  placing  the  pavilions 
on  a  north  and  south  line  or  axis,  because  the  slanting 
rays  of  the  sun  fall  in  the  morning  on  the  eastern  and  in 
the  evening  on  the  western  side." 

There  is  also  a  wide  variation  in  practice. 

In  a  list  of  thirty-eight  hospitals  given  in  Mouatt  & 
Snell's  work,  there  are  thirteen  in  which  the  pavilions  are 
placed  approximately  north  and  south;  fifteen  in  which 
they  are  placed  approximately  east  and  west;  six  in  which 
they  are  placed  approximately  northwest  and  southeast, 
and  four  in  which  they  are  placed  approximately  northeast 
and  southwest. 

Let  us  examine  the  questions  in  the  light  of  what  we  have 
already  learned  about  windows. 

For  an  example  we  shall  take  a  ward  with  unobstructed 
outlook,  having  ten  of  our  typical  windows  (3  ft.— 6  in.  by 
8  ft.-o.  in.)  on  each  side  and  none  at  the  ends. 


82 


ORIENTATION  OF  BUILDINGS 


Using  the  factors  in  Table  II,  giving  the  quantity  of 
sunlight,  in  "sun  hours,"  admitted  by  windows  of  different 
exposures,  we  obtain  the  following  results: 

TABLE   III 


Axis. 

Winter  Solstice. 

Equinoxes. 

Summer 
Solstice. 

North  and  south 

658 
1085 
1085 
1529 

1652 

1241 

1241 

811 

2214 

Northeast  and  southwest 

Northwest  and  southeast 

1266 

East  and  west 

230 

By  adding  three  windows  at  the  end  of  the  ward  the 
results  are  somewhat  modified,  as  shown  in  the  following 
table: 


TABLE   IV 


Axis. 

Winter  Solstice. 

Equinoxes. 

Summer 
Solstice. 

North  and  south 

1116. 7 
1410.5 
1410.5 
1627.7 

1895.8 
1557-5 
1557-5 
1058.8 

2262 . 6 

Northeast  and  southwest 

Northwest  and  southeast 

1426.2 

1426. 2 

562.I 

East  and  west 

In  both  cases,  the  ward  placed  with  its  axis  north  and 
south  receives  the  least  sunlight  in  winter,  when  sunlight 
is  most  needed,  and  the  maximum  in  summer,  when  it  is 
least  to  be  desired. 

In  the  east-and-west  position  the  results  are  reversed, 
showing  a  maximum  in  winter  and  a  minimum  in  summer. 

If  we  were  to  base  our  judgment  wholly  on  the  amount 
of  sunlight  received  by  windows,  we  should  be  led  to  follow 
the  conclusion  of  Dr.  Knauff,  that  the  best  position  for 
such  a  building  is  with  its  long  axis  placed  east  and 
west. 


HOSPITALS  83 


There  are  two  disadvantages,  however,  in  the  east-and- 
west  position;  the  first  that  it  involves  an  area  of  complete 
shadow,  on  the  north  side  of  the  building,  during  one-half 
the  year,  and  the  second  that  in  this  position  a  greater 
distance  is  necessary  between  the  pavilions  than  in  any 
of  the  other  positions  considered. 

The  north-and-south  position  has  all  of  the  disadvantages 
of  the  east-and-west  position  and  none  of  the  advantages. 
The  windows  admit  little  sunlight  in  winter  and  an  exces- 
sive quantity  in  summer.  If  conditions  make  it  necessary 
to  adopt  this  orientation,  the  wards  should  always  have 
windows  at  the  south  end. 

There  remain  to  be  considered  the  two  intermediate  posi- 
tions, northeast-southwest  and  northwest-southeast. 

In  both  of  these  there  is  little  variation  in  the  amount 
of  sunlight  received  at  different  seasons,  and  by  placing 
windows  at  the  southeast  or  southwest  end,  as  the  case 
may  be,  the  amount  of  sunlight  in  winter  is  very  much 
increased. 

Furthermore,  the  buildings  may  be  placed  closer  to- 
gether than  in  either  of  the  other  two  positions,  and  may 
be  so  planned  that  all  of  the  outside  walls  are  exposed  to 
the  sun  at  some  portion  of  the  day  throughout  the  year; 
and  this  advantage  is  obtained  not  only  for  the  wards, 
but  also  for  the  other  buildings  of  the  hospital  group, 
which  is  not  possible  where  a  north-and-south,  east-and- 
west  system  of  axes  is  adopted. 

As  between  the  northeast-southwest  and  the  northwest- 
southeast  positions,  the  only  difference  is  that  in  the  former 
the  broad  side  of  the  buildings  is  exposed  to  the  sunlight 


84 


ORIENTATION  OF  BUILDINGS 


in  the  forenoon,  while  in  the  latter  the  reverse  effect  is 
obtained.  This  indicates  a  slight  advantage  for  the  former, 
since  the  forenoon  sunlight  is  more  generally  prized  than  the 
afternoon  sunlight,  probably  because  it  is  constantly  in- 
creasing in  amount,  while  in  the  afternoon  it  is  constantly 
decreasing. 

We  are,  therefore,  led  to  recommend  that  for  hospital 
buildings  in  or  near  the  latitude  considered  in  this  book,  the 
long  axis  of  the  wards  should  be  placed  as  nearly  northeast 
and  southwest  as  possible,  and,  furthermore,  that  the  south- 
west ends  of  the  pavilions  should  always  have  windows. 


Fig.  48.  —  Illustrating  the  French  method  of  arranging  outside  blinds,  so  as  to 
fold  back  against  the  jamb.     This  is  the  ideal  arrangement  for  a  hospital  building. 

The  ward  windows  should  always  be  provided  with 
blinds,  shutters,  or  shades. 

Outside  blinds,  folding  back  against  the  jamb,  are  pro- 
tected from  the  wind  and  weather,  and  are  easily  reached 
from  the  inside.  With  a  window  of  3  ft. -6  in.  opening, 
which  goes  well  with  a  lineal  bed  space  of  8  ft.-o  in.,  a 
reveal  of  ten  inches  affords  the  requisite  space  for  outside 
blinds  of  this  type.  A  detail  of  the  arrangement  is  shown 
in  Fig.  48. 


HOSPITALS  85 

This  method  of  hanging  blinds  is  customary  in  France 
and  deserves  to  be  more  generally  used.  It  is  better  than 
the  American  method,  in  which  the  blinds  open  back 
against  the  outside  wall,  where  they  rattle  in  the  wind, 
are  exposed  to  the  sun  and  rain,  and  are,  moreover, 
exceedingly  troublesome  to  operate. 

The  ward  pavilion  is  the  unit  of  hospital  construction, 
and  the  essential  problem  in  planning  a  hospital  is  in  the 
design  and  grouping  of  these  units. 

The  typical  ward  unit  is  a  one-story  building,  although 
there  are  many  examples  of  hospitals  built  on  the  pavilion 
plan  in  which  the  pavilions  are  two,  and  even  three  stories 
in  height. 

There  is  an  economy  of  construction  in  the  super- 
position of  stories,  and  although  the  buildings  require  to 
be  placed  at  a  greater  distance  apart  to  secure  adequate 
sunlight,  there  is,  notwithstanding,  an  economy  of  land  as 
well. 

This  is  illustrated  in  Fig.  49  in  the  upper  part  of  which 
are  shown,  in  section,  four  one-story  pavilions,  spaced  at 
a  distance  apart  equal  to  one  and  one-half  times  their 
height.  In  the  lower  part  of  the  same  diagram  are  shown 
two  pavilions  of  two  stories  each,  also  at  a  distance  apart 
equal  to  one  and  a  half  times  their  height. 

The  number  of  patients  accommodated  is  the  same  in 
both  arrangements,  but  the  amount  of  land  required  for 
the  two-story  pavilions,  although  the  distance  between 
them  is  greater,  is  less  than  for  the  one-story  pavilions. 

If  we  consider  not  only  the  cross  section,  but  also  the 
plan,  a  further  economy  will  appear  in  favor  of  the  two- 


86 


ORIENTATION  OF  BUILDINGS 


story  arrangement;  for,  the  length  of  the  buildings  remain- 
ing the  same  in  both  cases,  an  increase  of  distance  between 
them  reduces  the  proportional  depth  of  the  U  court  between 
the  buildings,  making  it  more  open  to  the  sun.  It  follows, 
therefore,  that  the  distance  between  pavilions  should  be 
governed,  in  part  at  least,  by  their  relative  length,  as  well 
as  their  relative  height,  and  it  may,  therefore,  be  justifiable 
to  place  two-story  pavilions  at  a  less  distance  apart  in 
proportion  to  their  height,  than  one-story  pavilions  of  the 
same  length. 


Fig.  49.  —  Illustrating  the  economy  of  land  in  the  two-story  type  of  hospital 

building. 

While  economy  is  of  importance  in  hospital  construc- 
tion, it  must  always  be  kept  subordinate  to  the  welfare 
of  the  patient,  for  that  is  the  whole  end  and  aim  of  the 
hospital. 

"L'hopital  en  effet  n'a  qu'un  seul  but:  chercher  a  guerir, 
et  tout  doit  y  concourir.  .  .  .  Et  ici  plus  que  partout 
ailleurs,  l'economie  est  sacree,  car  si  pour  la  meme  somme 
on  peut  assurer  quelques  lits  de  plus,  c'est  de  l'impuissance 


HOSPITALS  87 

finale  de  l'assistance  publique  diminuee  d'autant.  Mais 
l'economie  ne  doit  etre  cherchee  au  detriment  de  l'hygiene: 
une  economie  sur  l'ornementation  d'une  facade  est  un 
vertu:  une  economie  sur  le  cube  d'air  des  malades  serait  un 
crime.  L'hopital  est  fait  pour  le  malade,  voila  ce  qu'il  ne 
faut  jamais  perdre  de  vue."  1 

In  all  respects  is  the  one-story  pavilion  the  best  for  the 
patient,  but  especially  because  it  is  best  adapted  to  ven- 
tilation by  natural  means. 

"The  amount  of  fresh  air  renewed  by  natural  ventilation 
is  infinitely  greater  than  that  which  can  be  obtained  by 
the  most  costly  mechanical  contrivances.  Thus,  in  a  room 
of  the  capacity  of  1500  cubic  meters  (nearly  53,000  cubic 
feet)  the  air  can  be  renewed  by  the  opening  of  a  single 
window  in  less  than  half  an  hour,  with  a  velocity  equal  to 
0.50  m.,  or  nearly  two  feet,  in  every  second."  (M.  Toilet, 
quoted  in  Mouatt  &  Snell's  Hospital  Construction  and 
Management.) 

Artificial  or  forced  ventilation,  which  in  our  climate  is 
a  necessary  evil  during  a  large  part  of  the  year,  may  be 
successfully  adapted  to  a  building  of  superposed  stories, 
as  well  as  to  a  subway  or  a  mine.  But  for  ventilation  by 
natural  means  nothing  has  ever  been  designed  so  effective 
as  ridge  or  monitor  ventilation  (Fig.  50),  in  conjunction 
with  open  windows,  a  method  of  construction  which  is,  of 
course,  not  possible  where  one  ward  is  superposed  upon 
another,  except  for  the  uppermost  story. 

Several  types  of  ward  pavilions  are  shown  in  Fig.  51. 
Nos.  1  and  2  are  single  pavilions  of  the  open-ended  type; 

1  Elements  et  Theorie  de  L'Architecture.    J.  Gaudet,  Paris. 


ORIENTATION  OF  BUILDINGS 


No.  3  a  double  pavilion,  and  No.  4  a  single  pavilion,  both 
with  closed  ends. 

Nos.  1  and  2  differ  only  in  the  position  of  the  corridor, 
which,  in  No.  1  runs  through  the  service  portion  of  the 
pavilion;1  and  in  No.  2  is  placed  clear  of  the  building. 


Fig.  50.  —  Illustrating  the  method  of  ridge  ventilation  for  hospital  ward 

pavilions. 

This  is  a  cross  section  of  the  one-story  wings  of  the  plan  shown  in  Fig.  58. 
(The  arched  form  is  advantageous,  but  is  not  essential.) 


The  advantage  of  the  latter  arrangement  is  that  any 
pavilion  of  a  group  may  be  reached  without  passing  through 
any  of  the  others,  and  the  circulation  through  the  corridor 
is  unimpeded  by  doors. 

1  In  all  the  figures  the  service  portion  is  indicated  by  shading. 


HOSPITALS 


*9 


■ 


\=J 


%=£ 


1=£ 


tlJ 





I  I 


0  50 

l 1_ 


100             150            200 
, I i I 


r 


3 


3  4 

Fig.  51.  —  Illustrating  several  types  of  ward  pavilions. 


9° 


ORIENTATION  OF  BUILDINGS 


Furthermore,  when  a  series  of  pavilions  of  the  type  of 
No.  I  are  connected  together,  a  series  of  U  courts  is  created, 
facing  in  opposite  directions,  involving  an  area  of  complete 
shadow  in  one  or  the  other. 

No.  2  is  free  from  this  objection. 

No.  3  is  the  type  of  pavilion  adopted  in  the  Virchow 
Hospital  in  Berlin.1  It  consists  of  two  one-story  wards 
joined  by  a  central  service  portion  two  stories  in  height,  in 
the  upper  part  of  which  are  lodged  the  nurses  who  have 
charge  of  the  pavilion. 

This  type  of  pavilion  was  not  designed,  and  is  not  suit- 
able for,  corridor  connection  and  is  therefore  not  likely 
to  be  adopted  in  our  climate,  where  it  is  considered  essen- 
tial that  the  pavilions  should  be  connected  by  corridors. 

In  both  Nos.  3  and  4  the  ends  of  the  wards  are  blocked 
by  service  rooms  and  in  No.  4  (Friedrichshain)  these 
service  rooms  project  so  far  as  to  cut  off  both  air  and  sun- 
light from  the  ward. 

Pavilions  may  be  grouped  in  various  ways. 

Fig.  52  is  typical  of  the  arrangement  adopted  at  the 
Virchow  Hospital.  It  will  be  noted  that  the  individual 
pavilions  are  placed  quite  close  together  and  yet  have 
access  to  large  open  spaces  on  either  side. 

There  seems  to  be  no  good  reason  why  the  pavilions 
of  a  general  hospital  should  be  placed  any  farther 
apart  than  is  necessary  to  secure  adequate  sunlight  and 
a  free  passage  of  air  between  them.  Compactness  saves 
steps  and  helps  toward  economy  of  administration. 
Furthermore,    too   great  a   space   between  pavilions  is   a 

1  Opened  in  1906.     Architect,  Dr.  Ludwig  Hoffmann. 


HOSPITALS 


91 


:=3 
n 


100 

1 


200  300  400  500 


Fig.  52.  —  Arrangement  of  ward  pavilions,Virchow  Hospital. 

In  the  entire  hospital  there  are  twenty  of  these  pavilions,  besides  others  of  a 
different  type. 


Q2 


ORIENTATION  OF  BUILDINGS 


u 


400 


Fig.  53.  —  Two  common  methods  of  grouping  ward  pavilions.     Neither  one  is 

recommended- 


HOSPITALS  93 

temptation  to  future  boards  of  trustees,  under  the  demands 
for  increased  accommodation,  to  fill  up  these  spaces  with 
new  buildings. 

Fig.  53  illustrates  two  dispositions,  both  of  which  are 
symmetrical  in  the  narrow  sense  of  the  word,  and  both  of 
which  are  bad,  since  they  involve  U  courts  facing  in  opposite 


0  TOO  200  300  400 

FEET 

Fig.  54  —  A  good  method  of  grouping  ward  pavilions. 

directions,  and  a  disparity  in  the  amount  of  sunlight  re- 
ceived by  the  opposite  wards. 

The  arrangement  shown  in  Fig.  54  is  more  truly  sym- 
metrical, since  all  of  the  wards  present  the  same  exposure 
to  the  sun,  and  it  is  recommended  as  the  best  arrangement 
for  single  pavilions  of  the  open-end  type. 


94  ORIENTATION  OF  BUILDINGS 

Fig.  55  shows  a  good  arrangement  of  buildings  where 
the  size  of  the  lot  does  not  allow  of  the  double  corridor 
plan. 

The  axes  of  the  buildings  are  placed  very  nearly  northeast  and  southwest  and 
the  shadows  are  shown  for  noon,  at  the  period  of  the  equinoxes. 

In  the  conventional  rendering  of  architectural  drawings  the  shadows  are  cast 
as  if  the  sun's  rays  came  from  the  left,  at  an  angle  of  450  with  the  plane  of  the 
picture,  both  in  plan  and  elevation. 

This  convention  is  assumed  irrespective  of  the  position  which  the  building  is 
to  occupy,  and  all  the  elevations  of  a  building  are  treated  as  if  they  faced  in  the 
same  direction.  A  facade,  for  instance,  having  a  northerly  exposure,  will  be 
represented  with  shadows  such  as  could  only  occur  on  a  south  facade,  and  an 
impression  of  abundant  sunlight  is  given  which  is  not  only  inaccurate,  but  false 
and  misleading. 

Such  a  departure  from  accuracy  and  truth  is  harmful  in  its  effect  upon  the 
student  and  a  careless  habit  is  engendered  of  regarding  the  architectural  drawing 
as  an  end  in  itself,  while  actual  conditions  of  site,  surroundings  and  exposure  are 
lost  sight  of.  So,  too,  has  grown  up  the  practice  of  studying  an  architectural 
plan  irrespective  of  its  orientation.  So  little  is  this  matter  regarded  that  it  is  the 
exception,  rather  than  the  rule,  to  find  the  points  of  the  compass  marked  upon  an 
architectural  plan. 

The  study  of  shades  and  shadows  is  regarded  so  entirely  for  its  use  in  the  con- 
ventional rendering  of  the  elevation  that  it  is  seldom  applied  to  the  rendering  of 
the  plan,  although  it  is  here  that  its  greatest  usefulness  is  found,  especially  in  the 
study  of  groups  of  buildings,  or  for  the  representation  of  landscape  work.  In  no 
other  way  may  the  relative  heights  of  buildings,  or  changes  in  level  of  a  site,  be 
so  graphically  shown  in  a  single  drawing. 

The  types  of  pavilion  so  far  illustrated  are  not  well 
adapted  to  the  requirements  of  modern  medical  treatment. 
The  classification  of  patients  according  to  their  needs  can- 
not be  accomplished  in  a  building  containing  but  one  large, 
open  ward  with  one  or  two  single  rooms;  and  the  open-air 
treatment,  which  has  been  found  so  effectual  in  many  medical 
cases,  cannot  well  be  given  except  in  a  building  especially 
designed  for  that  purpose. 

The  program  has  changed  and  a  new  type  of  hospital 
construction  must  be  devised  to  meet  it. 


95 


96  ORIENTATION  OF  BUILDINGS 

The  requirements  for  a  modern  system  of  hospital  con- 
struction adapted  to  a  general  hospital  of  moderate  size 
may  be  stated  as  follows: 

The  pavilions  should  be  placed  no  farther  apart  (except 
for  contagious  cases)  than  is  necessary  to  secure  adequate 
sunlight  and  air. 

Adjacent  to  the  pavilions,  but  not  between  them,  should 
be  large,  open  areas  easily  accessible  to  the  patients.  (An 
admirable  example  of  such  an  open  space  is  the  famous 
Mittel  Allee  of  the  Virchow  Hospital.) 

Each  pavilion  should  provide  for  a  subdivision  of  the 
patients  within  itself  and  should,  therefore,  contain  at  least 
two  or  more  open  wards  of  moderate  size,  besides  a  number 
of  smaller  wards  and  single  rooms. 

All  of  the  open  wards  should  have  ridge  or  monitor 
ventilation,  and  therefore  one  ward  may  not  be  superposed 
upon  another. 

Ample  facilities  should  be  provided  for  open-air  treat- 
ment, and  these  facilities  should  be  of  two  kinds:  open 
terraces  or  balconies  opening  directly  from  the  wards,  for 
open-air  treatment  in  the  daytime;  and  roofed  balconies 
or  loggias,  which  may  be  screened  in  and  protected  with 
blinds,  affording  an  opportunity  for  patients  to  sleep  in 
the  open  air. 

Each  pavilion  should  have  a  day  room,  for  those  patients 
who  are  able  to  be  out  of  bed;  and  the  bathrooms,  lava- 
tories, and  other  service  rooms  should  be  ample  in  number 
and  in  size. 

The  working  out  of  such  a  program  will  naturally 
result  in   a  building   having  more  the  aspect  of  a  large, 


HOSPITALS  97 

private  house,  than  the  long,  narrow  buildings  which  we 
have  been  accustomed  to  associate  with  hospital  archi- 
tecture. 

The  ward  unit  about  to  be  described  has  been  designed 
to  fulfill  this  program.  It  is  an  attempt  to  adapt  what 
may  be  called  the  "Virchow  idea"  to  the  conditions  with 
which  the  American  architect  is  called  upon  to  deal,  of 
which  the  two  dominant  ones  are  the  covered  corridors 
between  the  buildings  required  by  our  climate  and  the 
compactness   in   plan   required   by   the   custom  of  build- 


A 


D    Q    DjoDODODDDDDDapi 


ODD 

ODD 


D  D  D 
D  D  D 


pioDDaDDQDaaQojD   D   D 


Fig.  56.  —  Elevation  of  the  Virchow  unit.  Each  of  these  units  is  virtually  a 
complete  hospital  in  itself,  the  central  pavilion  corresponding  to  the  administra- 
tion building  of  a  cottage  hospital.  Each  unit  provides  for  forty-six  beds,  as 
follows : 

Two  open  wards  of  twenty  beds  each;  two  separation  rooms  of  two  beds  each; 
two  separation  rooms,  one  bed  each. 


ing  hospitals  in  or  close  to  the  large  cities,  where  the 
cost  of  land  usually  makes  an  extended  pavilion  plan 
impracticable. 

It  has  been  noted  that  in  the  Virchow  unit  the  cen- 
tral portion,  containing  the  service  rooms,  is  two  stories 
high.  The  total  height  of  this  central  portion  is  not, 
however,  much  greater  than  that  of  the  wings,  since 
the  service  rooms  are  not  as  high  as  the  wards  (Fig. 
56). 


98 


ORIENTATION  OF  BUILDINGS 


The  principle  involved  in  this  arrangement  may  be 
extended  further  (Fig.  57),  resulting  in  what  may  be  called 
the  pyramidal  type  of  ward  construction,  in  which  each 
story  is  less  in  area  than  the  one  below.  Such  buildings 
may  be  placed  close  together  and  yet  have  adequate  sun- 
light, and  all  of  the  wards  may  have  ridge  ventilation. 


w 


w 


w 


Fig.  57.' — Diagrammatic  section  illustrating  the  "pyramidal"  type  of  ward. 
The  service  portion  is  indicated  by  the  letter  S,  and  the  wards  proper  by  the 
letter  W.  B  indicates  the  basement.  It  will  be  noted  that  all  the  wards  can 
have  ridge  ventilation.  The  idea  expressed  by  this  diagram  is  worked  out  in 
practical  form  in  the  plan  on  the  opposite  page,  in  which  the  one  story  wings 
have  been  turned  at  right  angles  to  the  main  structure,  forming  a  U  court. 


The  diagrams  and  plans  herein  presented  illustrate  a  ward 
unit  of  a  pyramidal  type  designed  by  the  author.  Figs.  58, 
59,  and  60  give  the  detailed  plans  of  each  floor,  and  the 
diagrams  of  Figs.  61,  62,  and  63  show  the  building  in  iso- 
metric projection,  with  the  shadows  as  they  would  be  at 
the  winter  solstice. 

The  general  plan  (Fig.  64)  illustrates  a  method  of  group- 
ing these  units  to  form  a  complete  hospital. 

The  basic  idea  of  the  pyramidal  type  of  ward  is  to  com- 
bine the  economic  advantages  of  the  three-story  building, 
and  its  adaptability  to  subdivision  of  patients,  while  re- 
taining the  most  valuable  feature  of  the  one-story  type, 
namely,  ridge  ventilation. 


HOSPITALS 


99 


^~l£ 


Fig.  58.  —  Pyramidal  type  of  ward  unit.  First-floor  plan.  A  cross  section  of 
the  one-story  ward  wings  (W)  is  shown  in  Fig.  50.  These  wings  are  higher 
studded  than  the  service  portion. 


References. 

C.  Connecting  corridors.  L.  Lavatories,  0/-0"  X  i3'-o".  S.  Laboratory,  0/-9" 
X  12-0".  L.  R.  Linen  room,  12-0"  X  12-6".  K.  Kitchen,  12-0"  X  15-6". 
E.  H.  Entrance  hall.  EL.  Elevator.  B.  R.  Bath  room,  0/-9"  X  12-0". 
H.  Hall.  D.  Day  room,  i4'-6"X25/-6".  W.  Wards,  26'-o"X45'-o".  T.  Open- 
air  terrace.     R.  Terraces  between  the  pavilions. 


IOO 


ORIENTATION  OF  BUILDINGS 


Fig.  59.  —  Pyramidal  type  of  ward  unit.     Second-floor  plan.    The  wards  (W) 
have  ridge  ventilation.    They  are  higher  studded  than  the  service  portion. 


References. 

W.  Wards,  22'-o"  X  32'-o".  P.  Private  rooms,  n'-o"  X  i2'-o"  and  o'-6"  X 
i2'-o".  K.  Kitchen,  i2'-o"  X  i6'-q".  I.  Linen  room,  8-0"  X  20-6".  B.  R. 
Bath  room,  7-0"  X  i2'-o".  T.  Patient's  toilet  room,  4-0"  X  8'-o".  L.  Lavatory, 
8'-o"  X  15-6".    H.  Hall.     F.  Fire  escape  stairway. 


HOSPITALS 


IOI 


Fig.  60.  —  Pyramidal  type  of  ward  unit.  Third-floor  plan.  The  ward  (W) 
has  ridge  ventilation  and  extends  up  to  the  roof,  as  does  also  the  open-air 
ward,  S.  B. 

References. 

W.  Ward,  io'-o"  X  19-0".  K.  Kitchen,  io'-o"  X  n'-o".  T.  Patient's  toilet 
room,  4'-o"  X  8'-o".  L.  Linen  room,  8'-o"  X  15-6".  H.  Hall.  S.  B.  Open- 
air  ward.     F.  Fire  escape  stairway. 


102 


ORIENTATION  OF  BUILDINGS 


The  height  from  floor  to  ceiling  of  an  open  ward  should 
never  be  less  than  twelve  feet  and  is  often  made  more 
than  this,  and  in  wards  of  the  type  shown  in  Fig.  50  it  is 
necessarily  much  greater.     Assuming  thirteen  feet  in  the 


Fig.  61.  —  Pyramidal  type  of  ward  unit.     Shadow  diagram  10  a.m.,  winter 
solstice,  Lat.  42°-o'  N. 


clear  or  fourteen  feet  from  floor  to  floor,  for  wards  with 
flat  ceilings,  as  a  fair  average,  we  should  have  in  a  three- 
story  pavilion,  as  customarily  planned,  a  height  of  forty- 
one  feet  from  the  first-floor  level  to  the  ceiling  of  the  third 

floor. 


HOSPITALS  103 


If,  however,  we  adopt  what  I  have  called  the  Virchow 
idea,  of  building  the  second  story  over  the  service  portion 
of  the  first,  and  the  third  story  over  the  service  portion  of 
the  second,  at  the  same  time  reducing  the  height  of  the 


Fig.  62. —  Pyramidal  type  of  ward  unit.     Shadow  diagram  12  M.,  winter 
solstice,  Lat.  42°-o'  N. 

service  rooms  to  nine  feet  in  the  clear,  which  is  ample,  we 
shall  obtain  as  the  height  of  the  three-story  portion  of  our 
building,  from  the  first-floor  level  to  the  ceiling  of  the  third 
floor,  thirty- three  feet,  —  a  saving  of  eight  feet  over  the  cus- 
tomary construction. 


104  ORIENTATION  OF  BUILDINGS 

This  reduction  in  height,  combined  with  the  successive  re- 
duction in  area  of  each  story,  makes  it  possible  to  place  the 
buildings  at  the  minimum  distance  apart.  In  the  plan  (Fig. 
64)  the  distance  between  adjacent  pavilions  is  thirty-six  feet, 


FlG.  63.  —  Pyramidal  type  of  ward  unit.     Shadow  diagram  2  p.m.,  winter 
solstice,  Lat.  42°-o'  N. 

and  the  shadow  diagrams  (Figs.  61,  62,  and  63)  demonstrate 
that  this  distance,  with  the  orientation  adopted,  is  ample  to 
secure  adequate  sunlight,  even  at  the  winter  solstice. 

And  thus  the  first  requirement  of  our  program  is  satis- 
fied, that  the  distance  between  adjacent  pavilions  should 


HOSPITALS  105 

be  reduced  to  the  minimum  consistent  with  adequate  light 
and  air. 

Referring  to  the  general  plan  (Fig.  64),  it  will  be  seen 
that  between  the  two  groups  of  pavilions  extends  an  open 
space  of  ample  dimensions,  —  one  hundred  feet  wide,  and 
something  over  six  hundred  feet  long.  This  is  the  Mittel 
Allee  of  our  hospital.  Its  general  level  is  several  feet 
above  that  of  the  rest  of  the  grounds,  and  its  vista  is 
closed  at  one  end  by  the  Administration  Building,  a  low 
one-story  structure,  and  at  the  other  by  the  Chapel.  Be- 
tween the  first  group  of  pavilions  and  the  street  is  also  a 
wide,  open  space,  but  at  a  lower  level  than  the  other. 

And  thus  the  second  requirement  of  our  program  is  met, 
that  there  should  be  adjacent  to  the  pavilions,  but  not 
between  them,  large  areas  of  open  ground  easily  accessible 
to  the  patients. 

Each  of  the  pavilions  provides  for  forty-five  beds,  dis- 
posed as  follows,  in  wards  of  various  sizes,  aspects,  and 
conditions:  On  the  first  floor  two  open  wards  of  ten  beds 
each;  on  the  second  floor  two  open  wards  of  six  beds  each, 
and  three  single  rooms;  and  on  the  third  floor  one  open 
ward  of  four  beds  and  an  open-air  ward  of  six  beds. 

And  thus  the  third  requirement  of  our  program  is  met, 
that  the  pavilion  should  provide  for  a  proper  subdivision 
of  the  patients. 

The  two  open  wards  on  the  first  floor  are  of  the  arched 
section  shown  in  Fig.  50  and  provided  with  ridge  ventila- 
tion. The  two  open  wards  on  the  second  floor  have  slop- 
ing ceilings  following  the  slope  of  the  roof,  and  are  also 
provided  with  ridge  ventilation.     The  ward  on  the  third 


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108  ORIENTATION  OF  BUILDINGS 

floor  is  open  to  the  roof,  and  is  also  provided  with  ridge 
ventilation. 

And  thus  the  fourth  requirement  of  our  program  is  met, 
that  all  of  the  wards  should  have  ridge  ventilation. 

The  patients  on  the  first  floor  have  access  to  the  ter- 
races (T  and  R),  which  are  at  the  same  level  as  the  floor  of 
the  wards  and  overlook  the  Mittel  Allee,  which  is  reached 
by  a  gentle  incline  from  the  terraces  (R)  between  the 
pavilions.  The  roof  of  the  connecting  corridors  is  con- 
structed to  serve  as  a  terrace  for  the  patients  on  the  second 
floor,  while  the  patients  on  the  third  floor  have  the  open- 
air  balcony  or  loggia  (SB,  Fig.  60). 

And  thus  the  fifth  requirement  of  our  program  is  met, 
that  facilities  for  out-of-door  treatment  should  be  provided. 

The  roof  of  the  Hydrotherapeutic  Building  is  designed  to 
be  flat,  and  arranged  as  a  roof  garden,  affording  facilities 
for  the  true  sun  bath,  in  which  the  unclothed  body  is 
exposed  directly  to  the  sun's  rays. 

The  general  plan  (Fig.  64)  is  designed  to  illustrate  the 
adaptability  of  the  pyramidal  type  of  ward  unit  to  a  lot 
of  comparatively  restricted  dimensions.  It  consists  of  a 
series  of  U  courts  facing  southwest;  and  the  high  buildings 
of  the  service  and  administration  groups,  disposed  in  the 
same  general  shape,  are  so  placed  as  not  to  interfere  with 
the  sunlight  for  the  ward  pavilions.  The  entrance  court 
yard  (E)  and  the  service  court  yard  (S)  are  at  the  level 
of  the  surrounding  streets,  and  are  reached  by  arched 
entrances  at  the  basement  level;  the  main  entrance 
through  the  out-patient  block  (0-0)  and  the  service 
entrance    through    the  service   block   (D-L).     The  main 


HOSPITALS  109 


floor  level  of  the  buildings  is  one  story  above  the  level  of 
the  entrance  court  yards.  All  of  the  buildings  have  direct 
sunlight  on  all  of  their  exterior  walls  at  some  time  of  day 
throughout  the  year,  with  the  exception  of  one,  in  which 
there  is  a  small  area  of  complete  shadow.  This,  in  the 
light  of  previous  discussions,  the  reader  should  easily  be 
able  to  discover  —  and  suggest  a  remedy. 

It  will  be  noted  in  this  hospital  plan  that  the  direction 
of  the  streets  has  enabled  us  to  adopt  the  best  possible 
orientation  for  the  buildings.  If  the  streets  enclosing  our 
hospital  lot  had  been  laid  out  north  and  south,  east  and 
west,  it  would  have  been  a  difficult  matter  to  work  out  a 
satisfactory  plan. 

In  the  next  chapter  we  shall  point  out  the  principles 
which  should  govern  the  laying  out  of  streets. 


CHAPTER   IV 
Streets 

In  the  study  of  streets  there  are  two  matters  to  be  con- 
sidered; sunlight  and  sky  light.  Sky  light  comes  from 
all  directions  of  the  heavens;  sunlight  from  only  one  direc- 
tion, constantly  varying  with  the  revolution  of  the  sphere. 
The  direction  or  orientation  of  the  street  affects  the  sun- 
light particularly:  the  height  of  the  buildings  bordering 
upon  it  affects  both. 

To  investigate  the  distribution  of  sunlight  in  streets  we 
shall  employ  a  method  similar  to  that  used  in  obtaining 
the  shadow  curves  of  the  cube,  and  to  simplify  the  problem 
the  buildings  on  either  side  will  be  assumed  to  be  built  in 
blocks  of  uniform  height,  extending  continuously  in  both 
directions. 

Fig.  66  is  the  cross  section  of  such  a  street  running  north 
and  south;  Fig.  67  a  similar  street  running  southeast  and 
northwest,  and  Fig.  68  a  similar  street  running  east  and 
west. 

The  full  lines  give  the  angle  of  inclination  of  the  plane  of 
the  sun's  rays  at  the  period  of  the  equinoxes,  and  since  at 
this  period  of  the  year  the  sun's  rays  fall  in  the  same  plane 
throughout  the  day,  the  cross  section  of  the  east  and  west 
street,  being  at  right  angles  with  this  plane,  shows  the  same 
inclination  for  every  hour. 

The  distribution  of  the  sunlight  may  also  be  shown  by 


STREETS 


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ORIENTATION  OF  BUILDINGS 


sunlight  curves.     The  method  of  obtaining  these  curves  is 
shown  in  Fig.  69. 

This  is  a  cross  section  of  a  street  running  southeast- 
northwest,  taken  looking  northwest. 


(.  tfre_Sun ^ 


Fig.  69.  —  Cross  section  of  street  running  southeast  and  northwest,  looking 
northwest.  The  angles  of  sunlight  are  shown  as  they  would  be  at  the  summer 
solstice.     Lat.  42°-o'  N. 


The  dotted  lines  represent  the  plane  of  the  sun's  rays 
at  the  hours  noted.  It  is  clear  that  the  point  of  inter- 
section of  these  lines  first  comes  into  sunlight  at  9  a.m., 
remaining  in  sunlight  until  5  P.M.,  a  period  of  eight 
hours. 


STREETS  115 

By  finding  a  series  of  such  points  and  connecting  them, 
we  shall  obtain  the  curve  shown,  each  point  of  which  is  in 
sunlight  for  eight  hours,  and  may,  therefore,  be  called  the 
"eight-hour  curve." 

It  is  in  this  way  that  the  following  series  of  diagrams 
have  been  drawn  (Fig.  70). 

These  diagrams  give  the  complete  series  of  sunlight 
curves  at  the  typical  seasons  of  the  year,  for  streets  run- 
ning north-south,  east-west,  and  at  an  angle  of  450  with 
the  meridian. 

In  these  diagrams  the  height  of  the  buildings  is  rep- 
resented as  one  and  one-half  times  the  width  of  the 
street. 

The  diagrams  show  a  great  difference  in  the  amount  of 
sunlight  received. 

In  the  north-south  street  the  distribution  is  symmetrical, 
the  buildings  on  either  side  receiving  an  equal  amount. 

In  the.  east-west  street  the  surface  of  the  street  receives 
no  sunlight  at  all  during  six  months  of  the  year,  and  the 
buildings  on  the  south  side  of  the  street  are  in  perpetual 
shadow  during  the  same  period. 

In  city  planning  the  east-west  street  should  be  avoided 
as  far  as  possible,  and  where  unavoidable  the  buildings, 
especially  on  the  south  side,  should  be  of  moderate  height, 
and  built  in  detached  blocks,  so  as  to  admit  the  sunlight 
between  them. 

When  streets  are  laid  out  at  right  angles  to  each  other 
according  to  the  "checkerboard"  plan,  the  best  distribution 
of  sunlight  is  obtained  when  one  series  of  streets  runs  north- 
east-southwest and  the  other  riorthwest-southeast. 


n6 


ORIENTATION  OF  BUILDINGS 


^ 


Fig.  70.  —  Sunlight  curves  in  streets.  Ihe  three  upper  diagrams  are  for  a 
street  running  north  and  south,  the  three  middle  diagrams  for  a  street  running 
east  and  west,  and  the  three  lower  diagrams  for  a  street  running  at  an  angle  of 
45  degrees  with  the  meridian.  The  diagrams  of  the  left-hand  column  are  drawn 
for  the  winter  solstice;  of  the  center  column  for  the  vernal  and  autumnal  equinox; 
and  of  the  right-hand  column  for  the  summer  solstice.  ,  The  zones  between  the 
curves  are  shaded  in  a  series  of  tints,  the  lightest  zone  being  in  sunlight  between 
eight  and  nine  hours,  and  the  solid  black  being  without  sunlight. 


STREETS  117 

This  arrangement  was  recommended  many  years  ago  by 
Horace  Bushnell. 

In  his  essay  on  City  Plans1  occurs  the  following  passage: 

"It  is  also  a  great  question,  as  respects  the  health  of  the 
city,  in  what  direction,  or  according  to  what  points  of  the 
compass,  the  streets  are  to  be  laid.  To  most  persons  it 
will  appear  to  be  a  kind  of  law  that  the  city  should  stand 
square  with  the  cardinal  points  of  the  compass,  —  north 
and  south,  east  and  west.  And  where  this  law  appears 
not  to  have  been  regarded,  how  many  will  deplore  so  great 
an  oversight,  and  even  have  it  as  the  standing  regret  of 
their  criticism.  Whereas,  in  the  true  economy  of  health 
and  comfort,  no  single  house  or  city  should  ever  stand 
thus,  squared  by  the  four  cardinal  points,  if  it  can  be 
avoided.  On  the  contrary,  it  should  have  its  lines  of 
frontage  northeast  and  southwest,  northwest  and  south- 
east, where  such  a  disposition  can  be  made  without  injury 
in  some  other  respect;  that  so  the  sun  may  strike  every 
side  of  exposure  every  day  in  the  year,  to  dry  it  when  wet 
by  storms,  to  keep  off  the  mould  and  moss  that  are  likely 
to  collect  on  it,  and  remove  the  dank  sepulchral  smell  that 
so  often  makes  the  tenements  of  cities  both  uncomfortable 
and  poisonous  to  health." 

It  is  unfortunate  that  in  so  many  cases  where  the 
"checkerboard"  plan  has  been  adopted,  the  streets  have 
been  laid  out  north-south  and  east-west,  which  is  the 
worst  arrangement  possible. 

The  effect  of  tall  buildings  in  cutting  off  sunlight  and 
sky  light  from  buildings  on  the  opposite  side  of  the  street, 

1  Work  and  Play,  Horace  Bushnell,  N.Y.,  Charles  Scribner,  1864. 


Il8  ORIENTATION  OF  BUILDINGS 

and  from  the  street  itself,  is  considerable,  and  in  the 
building  laws  of  most  European  cities  a  definite  relation 
has  been  established  between  the  width  of  the  streets  and 
the  height  of  the  buildings  which  may  be  built  upon  them. 

An  admirable  example  of  such  a  regulation  is  found  in 
the  building  laws  of  Paris,  in  which  the  matter  is  worked 
out  with  a  precision  and  completeness  well  worthy  of 
study.1 

The  accompanying  diagram  (Fig.  7.1)  illustrates  its  appli- 
cation to  a  street  16  meters  (52.48  feet)  in  width. 

The  main  structure  of  the  building  must  be  built  within 
the  limits  of  the  heavy  enclosing  line,  which  is  determined 
as  follows: 

The  height  of  the  vertical  AA  is  taken  at  6  meters  plus 
the  width  of  the  street,  for  streets  less  than  12  meters  in 
width,  and  for  streets  over  that  width  it  is  taken  at  18 
meters,  plus  one-quarter  of  the  amount  by  which  the  width 
of  the  street  exceeds  12  meters,  but  must  not  exceed  20 
meters  (65.60  feet)  in  any  event.  For  a  street  of  16  meters 
the  height  AA  will,  therefore,  be  19  meters  (63.32  feet). 

From  the  top  of  this  line  a  circular  arc  is  drawn,  and 
tangent  to  it  a  line  of  450  inclination.  This  tangent  is 
extended  until  it  meets  a  vertical  halfway  back  in  the 
building  or  until  it  meets  a  similar  tangent  determined  by 
the  frontage  of  the  rear  portion  of  the  building. 

The  radius  of  this  arc  is  taken  at  one-half  the  width  of 
the  street,  but  may  not  exceed  10  meters  (32.80  feet)  in 
any  event. 

A  similar  regulation  governs  the  rear  facade  of  the  build- 

1  The  Paris  law  is  given  in  full  in  Appendix  B, 


STREETS 


IIQ 


ing  and  also  all  frontages  on  light  courts  and  areas,  the 
result  being  an  abundance  of  light  and  air  throughout  the 
structure. 


Fig.  71.  —  Diagram  illustrating  the  building  regulations  of  Paris,  applying  to 
the  height  of  buildings.  The  vertical  A-A  and  the  radius  of  the  circular  arc  vary 
with  the  width  of  the  street.  The  horizontal  B-B  marks  the  limit  of  height  for 
party  walls,  and  the  vertical  line  above  the  curve  and  just  back  of  the  front  wall 
line,  marks  the  setback  for  chimneys.  The  lighter  enclosing  lines  beyond  the 
heavy  line  mark  the  limit  of  projection  for  balconies,  cornices,  and  other  projec- 
tions from  the  main  structure. 

In  England  the  matter  is  regulated  in  two  ways:  directly, 
by  building  by-laws  limiting  height,  varying  in  different 
cities  and  for  different  classes  of  buildings;  and  indirectly, 


120  ORIENTATION  OF  BUILDINGS 

by  the  statute  law  of  ancient  lights.  Under  this  law  an 
owner  or  tenant  of  a  building  may  acquire  a  right  to  light 
coming  across  the  property  of  another,  just  as  in  this  country 
a  right  of  way  across  the  land  of  another  may  be  acquired 
by  prescription. 

"Cujus  est  solum  ejus  est  usque  ad  ccelum"  is  an  ancient 
maxim  of  our  common  law,  and  in  the  words  of  an  English 
writer,  "An  interference  with  the  space  superincumbent 
on  a  man's  land  is  an  injury  for  which  the  law  provides 
a  remedy." 

In  England  the  deprivation  of  light  is  regarded  as  such 
an  interference,  actionable  at  law,  but  in  this  country  the 
individual  owner,  where  not  restrained  by  specific  statutes, 
is  allowed  to  build  as  high  as  he  pleases,  regardless  of  the 
injury  done  to  his  neighbors  and  to  the  public,  and  even 
the  right  of  a  municipality  to  impose  a  limit  to  the  height 
of  buildings  has  been  contested. 

A  recent  decision  (May  17,  1909)  of  the  Supreme  Court,1 
however,  upholds  the  constitutionality  of  such  building 
laws,  and  even  that  city  which  has  taken  a  mistaken  pride 
in  having  originated  the  "skyscraper"  type  of  architecture 
has  recently  imposed  a  maximum  limit  of  210  feet  to  the 
height  of  its  buildings. 

In  my  own  city  of  Boston  a  law  has  been  in  force  since 
1892  limiting  the  height  of  buildings  generally  to  two  and 
one-half  times  the  width  of  the  street,  with  a  maximum 
limit  of  125  feet;  and  subsequent  legislation  has  reduced 
this  limit  in  certain  districts  of  the  city. 

1  Welch  vs.  Board  of  Appeal  of  the  City  of  Boston.  U.  S.  Reports,  Vol.  CCXIV, 
page  91. 


STREETS  121 

The  regulations  of  some  other  American  cities  in  this 
regard  are  given  in  Appendix  C. 

The  method  of  limiting  the  height  of  buildings  by  a 
horizontal  plane,  either  at  a  fixed  height,  or  at  a  height 
proportional  to  the  width  of  the  street,  is  simple  in  appli- 
cation but  is  not  scientific,  since  it  assumes  that  what  is 
the  proper  height  for  the  front  wall  or  facade  is  also  the 
proper  height  for  the  rear  portions  of  the  building;  whereas, 
as  a  matter  of  fact,  the  rear  portions  may  well  be  allowed 
to  rise  to  a  greater  height,  in  proportion  to  their  distance 
back  from  the  street  line. 

This  method  also  results  in  an  uninteresting  and  hard 
type  of  architecture.  The  land  owner,  intent  on  securing 
every  foot  of  rentable  space,  duplicates  one  story  on  top 
of  another,  with  the  usual  result  that  the  cornice  is  forced 
above  the  level  of  the  real  roof  as  shown  in  Fig.  72,  cutting 
off  the  sunlight  and  darkening  the  street  unnecessarily. 

This  false  position  of  the  cornice  constitutes  the  dis- 
tinguishing mark  of  ordinary  American  civic  architecture, 
and  is  the  direct  result  of  unscientific  building  laws. 

Although  a  building  law  designed  solely  for  the  purpose 
of  securing  an  aesthetic  effect  would  probably  be  decided 
to  be  unconstitutional  in  this  country,  it  fortunately  hap- 
pens that  in  the  matter  of  regulating  the  height  of  build- 
ings, that  method  which  naturally  results  from  a  scientific 
study  of  the  question  of  sunlight  also  tends  to  produce  the 
best  type  of  architecture. 

A  method  which  has  been  proposed  by  several  architects, 
and  which  has  also  been  advocated  by  the  writer,  is  illus- 
trated in  Fig.  73. 


122 


ORIENTATION  OF  BUILDINGS 


Under  this  plan  the  height  of  the  building  is  limited  by 
a  slanting  line  drawn  from  the  opposite  side  of  the  street 
at  a  certain  angle.     This  angle  should  be,  in  the  opinion 


Fig.  72.  —  This  type  of  cornice  is  typical  of  x\merican  commercial  architecture. 
It  is  not  really  a  cornice  but  a  distorted  parapet  wall,  and  is  also  bad  from  the 
practical  point  of  view  because  it  cuts  off  the  sunlight  unnecessarily.  It  is  the 
direct  result  of  unscientific  building  laws,  which  apply  the  limit  of  height  to  the 
highest  point  of  the  roof,  often  several  feet  below  the  top  of  the  exterior  walls  of 
the  building. 


of  the  writer,  such  that  the  height  of  the  front  wall  of  the 
building  should  not  exceed  one  and  one-quarter  times  the 
width  of  the  street,  and  it  is  so  shown  in  the  diagram. 


STREETS 


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124 


ORIENTATION  OF  BUILDINGS 


In  addition  to  the  slanting  line  the  extreme  height  of  the 
roof  is  limited  by  a  horizontal  plane  at  a  height  uniform 
for  all  buildings,  irrespective  of  the  width  of  the  street. 


Fig.  74.  —  The  skyscraper  and  the  street.  The  left-hand  diagram  is  a  cross 
section  of  a  street  bordered  by  buildings  of  reasonable  height;  the  right-hand 
diagram  a  street  with  a  wall  of  sky  scrapers  on  either  side.  The  street  is  supposed 
to  run  east  and  west  and  the  shadows  show  the  angle  of  sunlight  throughout  the 
day,  at  the  vernal  and  autumnal  equinox.    Lat.  42°-o'  N. 


A  similar  method  may  well  be  adopted  to  regulate  the 
walls  of  the  building  fronting  on  light  courts  and  areas,  and 
for  this  purpose  an  angle  of  less  inclination  from  the  vertical 
may  be  justified. 

In  discussing  the  question  as  to  what  should  be  the  limit 
of  height  of  buildings  in  cities  it  is  proper  to  assume  that 
both  sides  of  the  street  will  in  time  be  built  up  to  whatever 
limit  is  decided  upon.     The  effect  of  a  few  scattered  tall 


STREETS  125 

buildings  in  darkening  the  streets  is  not  serious,  but  the 
effect  of  a  solid  wall  of  skyscrapers  would  be  extremely  so. 
In  the  accompanying  diagrams  (Fig.  74)  is  shown  the 
section  of  a  street  60  feet  wide,  in  the  one  case  bordered 
with  buildings  250  feet  high  and  in  the  other  with  buildings 
regulated  in  accordance  with  the  building  law  proposed  by 
the  author.  Which  of  the  two  should  be  typical  of  the 
American  city  planning  of  the  twentieth  century  is  left  to 
the  judgment  of  the  reader. 


APPENDIX   A 


Sun  Tables 


Winter  Solstice. 

Equinoxes. 

Summer  Solstice. 

Hour  angle. 

Az. 

Alt. 

Az. 

Alt. 

Az. 

Alt. 

120° 

1270  42' 

i°  21' 

I05  ° 

Il6°  4' 

9°  3o' 

90° 

900  0' 

o°  0' 

105°  7' 

180  7' 

75° 

780    10' 

9°  23' 

94°  0' 

270  20' 

6o° 

65°  4l' 

180  5' 

820  2' 

36 °  40' 

45° 

400  40' 

5°  14' 

51°   57' 

260  6' 

68°  10' 

45°  39' 

3°° 

27°  59' 

io°  25' 

36°    25' 

32°  36' 

So°  48' 

53°  43' 

iS° 

140  9' 

13°  48' 

18°  54' 

36°  58' 

280  2' 

59°  4o' 

o° 

o°  0' 

15°  3' 

o°  0' 

38°  30' 

o°  0' 

6i°  57' 

Sunrise  and  Sunset 


3h. 

48  m. 

5o°  16' 

o°  0' 

6h. 

0  m. 

900  0' 

o°  0' 

8h. 

12  m. 

129°  44' 

o°  0' 

London.     Lat.  510  30'  N. 


126 


APPENDIX  A 


127 


Winter  Solstice. 

Equinoxes. 

Summer  Solstice. 

Hour  angle. 

Az. 

Alt. 

Az. 

Alt. 

Az. 

Alt. 

90° 

9o°  0' 

o°  0' 

«o°  35' 

11°   27' 

75° 

62 °   24' 

o°  22' 

820  22' 

12°    57' 

1040  18' 

23°    52' 

6o° 

54°  9' 

ii°  20' 

73°  54' 

25°    39' 

980  16' 

360  36' 

45° 

44°  7' 

21°    16' 

63 °  26' 

37°  46' 

9i°  47' 

49°  32' 

3o° 

3i°  44' 

29°    3' 

49°  6' 

48 °  36' 

83°  27' 

620  30' 

15° 

16°  47' 

34°  4i' 

280  11' 

56°  47' 

67°  29' 

75°  6' 

o° 

o°  0' 

36°  33' 

o°  0' 

60°  0' 

o°  0' 

83°  27' 

Sunrise  and  Sunset 


5  h.      2m. 

6  h.      o  m. 
6  h.    58  m. 


620  38' 


90 


117"  22' 


New  Orleans.     Lat.  300  o'  N. 


APPENDIX    B 


DECREE  REGULATING   THE  HEIGHT  OF  BUILDINGS  AND 

PROJECTIONS  FROM   THE   SAME  IN  THE   CITY 

OF  PARIS.    August  13,  1902 

Article  i.  The  limits  beyond  which  buildings  upon  the  public  ways 
of  Paris  are  not  allowed  to  project  is  fixed:  first:  by  two  "limiting  cross 
sections"  established,  one  for  the  structure  proper,  and  the  other  for  pro- 
jections forming  an  integral  part  of  the  structure;  second:  by  special  rules 
set  forth  under  Title  II,  Sections  III  and  IV  of  this  decree,  for  projections 
not  forming  an  integral  part  of  the  structure. 

TITLE  I 
HEIGHTS  OF  BUILDINGS 

First  Section.     Buildings  on  Public  Ways 

Art.  2.  The  "limiting  cross  section"  of  the  structure  proper  is  deter- 
mined by  a  vertical  line  erected  on  the  front  line  of  the  lot. 

The  height  of  this  line,  measured  from  the  sidewalk  level  or  the  level  of 
the  pavement  at  the  foot  of  the  facade  and  taken  at  the  middle  point  of 
this  facade,  is  calculated  thus. 

For  streets  less  than  12  meters  (39.36  feet)  in  width,  the  height  must  not 
exceed  6  meters  (19.68  feet)  plus  the  width  of  the  street. 

For  streets  of  12  meters  and  over  this  height  must  not  exceed  iS 
meters  (58.64  feet)  plus  one-quarter  of  the  amount  by  which  the  width  of 
the  street  exceeds  12  meters,  but  must  not  in  any  case  exceed  20  meters 
(65.60  feet). 

In  calculating  this  height  a  fraction  of  a  meter  in  the  width  of  the  street 
is  taken  at  one  meter. 

On  sloping  streets  the  facade  of  the  buildings  is  divided  into  sections 
not  exceeding  30  meters  (98.40  feet)  and  the  height  of  each  section  is  taken 
in  the  middle. 

128 


APPENDIX   B  129 


In  the  case  of  several  distinct  buildings  the  height  of  each  is  taken  sepa- 
rately according  to  the  above  rules. 

Art.  3.  The  "limiting  cross  section"  referred  to  in  the  preceding  article 
is  completed  by  a  circular  arc,  tangent  to  the  vertical  line,  at  its  highest 
point,  and  by  another  line  tangent  to  this  circular  arc. 

The  radius  of  the  circular  arc  is  taken  at  half  the  width  of  the  street 
but  must  not  exceed  10  meters  (32.80  feet).  However,  for  streets  less 
than  12  meters  (39.36  feet)  it  need  not  be  reduced  to  less  than  6  meters 
(19.68  feet). 

The  other  line  referred  to,  tangent  to  this  circular  arc,  is  drawn  with  an 
inclination  of  45  degrees  until  it  meets  a  vertical  erected  in  the  middle  of 
the  depth  of  the  building,  taken  at  the  ground  floor  level. 

However,  it  is  allowed,  if  desired,  to  prolong  this  inclined  line  until  it 
meets  the  tangent  of  another  such  circular  arc  established  as  described 
above  on  the  highest  point  of  the  vertical  line  referred  to  in  Article  10. 
The  inclination  of  this  second  tangent  must  also  be  45  degrees. 

In  any  case,  excepting  for  chimney  stacks,  the  highest  point  of  party 
walls  between  two  buildings  must  not  be  built  more  than  one  meter  (3.28 
feet)  above  the  horizontal  tangent  of  the  circular  arc,  excepting  as  provided 
in  Article  6. 

Art.  4.  At  street  intersections  the  "limiting  cross  section"  is  deter- 
mined according  to  the  open  space  between  the  facades  at  such  inter- 
sections, taken  at  right  angles,  and  considered  as  the  width  of  the  street 
according  to  Article  2.  But  such  additional  height  is  allowed  only  for  that 
portion  of  the  facade  which  is  opposite  such  open  space. 

Nevertheless,  every  building  built  upon  a  corner  of  two  streets  of  unequal 
width,  whatever  may  be  their  level  or  slope,  may  be  built  upon  the  narrower 
street  up  to  the  height  allowed  for  the  wider  of  the  two,  provided  that  such 
additional  height  does  not  extend  back  on  the  narrower  street  for  a  distance 
greater  than  one  and  a  half  times  its  width. 

For  buildings  built  upon  a  corner  formed  by  two  streets  of  equal  width 
but  of  different  slopes,  the  height  is  taken  as  the  average  for  the  middle 
points  of  each  frontage.  But  frontages  on  which  the  height  is  taken  con- 
formably to  the  level  of  the  street  on  which  such  frontages  face,  as  for 
separate  buildings,  need  not  be  reckoned  in  determining  such  middle 
point. 


130  APPENDIX  B 


Art.  5.  For  buildings  comprised  between  streets  of  different  widths 
or  of  different  levels  the  "limiting  cross  section"  for  each  facade  must  be 
determined  by  the  street  upon  which  it  faces. 

However,  if  the  extreme  distance  between  two  such  facades  does  not 
exceed  15  meters  (49.20  feet)  the  facade  upon  the  narrower  or  lower  street 
may  be  built  up  to  the  "limiting  cross  section"  fixed  for  the  facade  upon  the 
wider  or  higher  street. 

Art.  6.  Chimney  stacks  may  not  be  built  more  than  one  meter  (3.28 
feet)  above  the  highest  point  of  the  "limiting  cross  section"  and  their 
front  face  must  be  at  least  one  meter  back  of  the  front  line. 

Art.  7.  For  portions  of  a  building  projecting  beyond  or  built  back  of 
the  general  building  line  the  "limiting  cross  section"  referred  to  in  Article  2 
is  based  upon  a  street  width  equal  to  the  distance  between  the  extreme 
projection  of  the  facade  and  the  street  line  opposite. 

In  such  calculations,  fractions  of  a  meter  are  taken  as  equal  to  a 
meter. 

Buildings  or  sections  of  buildings  built  at  the  ground  story  or  on  the 
stories  above,  back  of  the  street  fine,  may  be  built  within  the  "limiting 
cross  section"  permitted  for  a  street  the  width  of  which  is  equal  to  the 
distance  between  the  street  line  opposite  such  building  or  section  of  build- 
ing, provided  that  there  is  built  on  the  street  line  a  solid  and  substantial 
wall  at  least  one  meter  high. 

Art.  8.  Buildings  which  are  not  built  up  to  the  "limiting  cross  sec- 
tion" permitted  may  be  constructed  in  all  parts  as  the  builder  desires, 
provided  they  do  not  project  beyond  such  "limiting  cross  section." 

Second  Section.    Buildings  on  Areas  and  Courts 

Art.  9.  Courts  which  furnish  light  and  air  to  rooms  capable  of  being 
used  for  purposes  of  habitation,  either  in  the  daytime  or  at  night,  must 
have  an  area  of  30  meters  (322.80  square  feet)  at  the  least. 

For  courts  which  only  light  such  rooms  as  kitchens  the  minimum  area 
may  be  reduced  to  15  meters  (161.40  square  feet). 

Small  courts  or  "light  shafts"  serving  to  give  light  and  air  to  rooms 
which  cannot  be  used  for  purposes  of  habitation  must  have  an  area  of 
8  meters  (86.08  square  feet)  at  the  least. 


APPENDIX  B 


131 


Art.  10.  The  clear  space  opposite  each  window  of  a  room  serving  for 
day  or  night  habitation  must  not  be  less  than  is  provided  in  the  following 
table. 


Minimum  Area  of 
Court. 

Clear  Space. 

Minimum  Area  of 
Court. 

Clear  Space. 

Square  Feet. 
322.80 
358.63 
394.46 
430.40 
466. 23 

Feet. 
13.12 
14.  20 
15.28 
16.40 
17.48 

Square  Feet. 
502 . 06 
538.00 

573.83 
609.66 

Feet. 
18.56 
19.68 
20.76 

21  .84 

For  buildings  opposite  party  walls  the  minimum  clear  space  opposite 
windows  of  habitable  rooms  is  5  meters  (16.40  feet). 

The  "limiting  cross  section"  of  buildings  or  parts  of  buildings  situated 
on  courts,  composed  of  the  same  elements  as  indicated  in  Articles  2  and  3, 
is  determined  by  the  following  table. 


Minimum  Clear  Space. 

Maximum  Height  of 
Vertical. 

Maximum  Radius 
of  Arc. 

Square  Feet. 

Feet. 

Feet. 

13.12 

39   36 

19.68 

14.  20 

42.64 

21.32 

15.28 

45-92 

22  .96 

16.40 

49.  20 

24.60 

17.48 

52.48 

26.  24 

18.56 

55-76 

27.88 

19.68 

59-04 

29.52 

20.76 

62.32 

31.16 

21  .84 

65.60 

32.28 

Buildings  or  parts  of  buildings  built  in  retreating  stories  may  be  built 
in  each  story  according  to  the  "limiting  cross  section"  determined  sepa- 
rately for  that  story  according  to  the  clear  space  opposite  that  story. 

The  ground  level  of  every  court  is  considered  independently  of  that 
of  the  public  street  or  of  another  court. 

Stairway  towers  or  bays  arranged  in  such  courts  may  project  beyond 
the  "limiting  cross  section"  as  above  determined  up  to  the  ceiling  level  of 
the  highest  story  served  by  such  stairway. 


132 


APPENDIX  B 


Art.  ii.  In  the  case  of  courts  which  only  furnish  light  and  air  to  such 
habitable  rooms  as  kitchens,  the  dimensions  of  the  "limiting  cross  section" 
may  be  modified  as  per  the  following  table. 


Minimum  Area  of 

Minimum  Clear 

Maximum  Height  of 

Maximum  Radius 

Court. 

Space. 

Vertical. 

of  Arc. 

Square  Feet. 

Feet. 

Feet. 

Feet. 

.  161 .40 

6.56 

39 -36 

19.68 

179. 26 

7.08 

42.64 

21.32 

197.23 

7.64 

45-92 

22  .96 

215 . 20 

8.20 

49.20 

24.60 

233.06 

8.76 

52.48 

26.24 

251-03 

9.28 

55-76 

27.88 

269 . OO 

9.84 

59-04 

29.52 

286.86 

IO.36 

62  .32 

31.16 

304.83 

IO.92 

65.60 

32.28 

Art.  12.  The  vertical  walls  of  "light  shafts"  may  be  built  to  the 
height  determined  for  the  building  in  general. 

The  clear  space  opposite  windows  in  "light  shafts"  must  not  be  less  than 
1  m.  90  (5.33  feet). 

Kitchens  of  the  concierge  on  the  ground  floor  may  take  their  light  and 
air  from  "light  shafts." 

On  the  top  story  of  buildings  habitable  rooms  may  take  their  light  and 
air  from  "light  shafts." 

Art.  13.  In  any  case  the  minimum  area  of  light  courts  and  shafts  as 
determined  by  Article  9  may  not  be  diminished  by  new  construction  or 
selling  of  property. 

Art.  14.  Glass  roofs  may  not  be  built  over  light  courts  or  shafts  above 
the  rooms  which  take  their  light  and  air  from  them,  whether  rooms  of  habi- 
tation, kitchens  or  water  closets,  unless  such  glass  roofs  have  monitor 
ventilating  sash  with  a  clear  opening  of  at  least  one-third  the  area  of  the 
court  and  of  a  minimum  height  of  40  centimeters  (15.72  inches),  and  unless 
also  there  are  arranged  at  the  bottom  of  such  court  or  shaft  openings  com- 
municating with  the  cellar  or  basement  having  at  least  8  decimeters  (8.56 
square  feet)  of  area.  The  monitor  ventilation  is  not  required  for  light 
wells  and  shafts  unless  they  serve  habitable  rooms,  kitchens,  or  water 
closets;  but  light  shafts,  the  lower  part  of  which  does  not  communicate 
with  the  outer  air,  must  be  ventilated. 


APPENDIX  B  133 


Art.  15.  All  measurements  of  light  courts  and  shafts  must  be  taken 
on  the  work. 

Art.  16.  Owners  of  adjoining  buildings  who  may  have  made  an  agree- 
ment to  have  light  courts  and  shafts  in  common  may  build  them  of  the 
dimensions  prescribed  in  Articles  9,  10,  11,  and  12  for  light  courts  and  shafts 
belonging  to  a  single  building. 

They  must,  in  such  case,  notify  the  prefect  of  the  Seine  of  their  agree- 
ment and  execute  with  the  City  of  Paris,  before  commencing  the  work,  an 
agreement  to  maintain  such  courts  and  shafts  for  their  common  use. 

Such  courts  and  shafts  may  be  divided  by  walls  of  a  height  in  accordance 
with  article  663  of  the  civil  code. 

Third  Section.    Story  Heights 

Art.  17.  In  all  buildings  bordering  on  public  ways,  private  ways  or 
courts,  the  height  of  the  ground  story  and  that  of  the  next  above  must 
never  be  less  than  2  m.  80  (9.18  feet)  in  the  clear. 

The  height  of  basements  and  other  stories  must  never  be  less  than  2  m.  60 
(8.53  feet)  in  the  clear. 

For  the  top  story  of  a  building  this  last  height  applies  to  the  highest 
part  of  a  sloping  ceiling,  and  every  room  with  a  sloping  ceiling  in  part  must 
have  at  least  2  square  meters  (21.52  square  feet)  of  level  ceiling. 


TITLE  n 
PROJECTIONS  FROM  BUILDINGS 

First  Section.    In  General 

Art.  18.  No  projection  may  be  built  from  any  building  in  Paris, 
whether  on  the  street  line  or  not,  so  as  to  project  over  a  public  way,  other 
than  those  authorized  below. 

Art.  19.  For  buildings  on  the  street  line,  the  front  face  of  party  walls 
must  always  mark  the  street  line:  for  this  purpose  there  must  be  reserved, 
at  a  height  of  a  meter  and  a  half  above  the  ground,  a  level  surface  at  least 
20  centimeters  square. 

Art.  20.  Dimensions  of  projections  are  fixed  (saving  the  exceptions 
given  below)  according  to  the  width  of  the  street  opposite  the  building  if 


134  APPENDIX  B 


on  the  street  line,  and  according  to  the  effective  width  for  buildings  set 
back. 

All  projections  are  measured  from  the  street  line  for  buildings  upon  the 
street  line  and  from  the  ashlar  line  for  buildings  not  on  the  street  line. 

In  Reckoning  such  width,  fractions  of  a  meter  are  taken  as  one  meter. 

Second  Section.    Projections  of  Constructions  Forming  a  Part  of 
the  Building  Proper 

Art.  21.  The  limit  of  projections  from  the  facade,  for  decorative 
features,  foundations,  balconies  and  built-out  constructions,  is  determined 
by  a  "limiting  cross  section"  established  as  follows: 

This  "limiting  cross  section"  is  composed  of  two  vertical  lines,  one 
relating  to  the  upper  part  of  the  facade  from  a  point  taken  at  the  estab- 
lished height  as  determined  in  Article  2,  and  the  other  relating  to  the  lower 
part  of  the  facade. 

The  line  separating  these  two  parts,  for  streets  of  30  meters  (98.40  feet) 
and  over  is  placed  at  a  minimum  height  above  the  sidewalk  of  3  meters 
(9.84  feet),  and  for  streets  less  than  30  meters,  at  a  height  of  6  meters 
(19.68  feet)  less  one-tenth  of  the  width  of  the  street,  above  the  sidewalk. 

The  projection  of  the  "limiting  cross  section"  from  the  street  line  is  for 
the  upper  part  of  the  facade  8  centimeters  for  every  meter  in  the  width 
of  the  streets  up  to  streets  of  10  meters  in  width,  and  60  centimeters  plus 
ihs  of  the  width  of  the  street,  with  a  maximum  of  1  m.  20  (3.94  feet) 
for  streets  of  10  meters  and  over. 

The  projection  of  the  "limiting  cross  section"  for  the  lower  part  of  the 
facade  must  not  exceed  one-quarter  of  the  projection  of  the  upper  part, 
but  need  not  be  less  than  20  centimeters  (7.8  inches)  in  any  event. 

For  the  upper  part  of  the  facade,  the  plane  of  the  street  line  must  serve 
as  the  basis  of  all  decoration  and  occupy,  at  each  story,  one-tenth  at  least 
of  the  surface  of  the  facade  of  that  story,  after  deducting  bays. 

Art.  22.  There  may  be  established  upon  the  upper  part  of  facades, 
constructions  corbeled  out,  whose  gross  area,  projected  on  a  vertical  plane 
parallel  to  the  facade,  may  not  occupy  in  any  case,  more  than  one-third 
of  the  total  upper  part  of  said  facade. 

For  buildings  having  several  facades  upon  the  street,  each  facade  shall 
be  considered  separately  in  such  calculation. 


APPENDIX  B 


*35 


Each  dividing  section  counts  with  either  one  of  the  facades  which  it 

separates,  at  the  choice  of  the  constructor. 

Laterally,  and  at  the  ends  of  buildings,  the  projections  of  the  construc- 
tions are  limited  by  a  vertical  plane  forming  an  angle  of  45  degrees  with 
the  front  wall  and  intersecting  it  at  25  centimeters  (9.8  inches)  from  the 
party  line. 

Art.  23.  In  streets  of  16  meters  (52.48  feet)  of  width  and  over,  the 
established  projection  of  every  balcony  may  be  increased  one-quarter, 
provided  that  in  horizontal  projection  the  total  of  all  balconies  does  not 
cover  more  than  a  quarter  of  the  surface  permitted  at  each  story. 

Art.  24.  Notwithstanding  Article  21,  the  decoration  of  the  principal 
entrances  of  a  building  and  that  of  the  cornices  of  the  ground  story  may 
descend  to  a  height  of  2  m.  50  (8.20  feet)  above  the  sidewalk,  with  a 
projection  equal  to  twice  that  permitted  for  the  lower  part  of  the  facade. 

In  streets  of  20  meters  and  over,  the  decoration  of  the  principal  entrances 
may  descend  to  the  ground,  with  a  projection  not  over  twice  that  per- 
mitted for  the  lower  part  of  the  facade. 

Art.  25.  Iron  guards  and  other  similar  objects  of  iron- work  intended  to 
serve  as  defences  on  balconies  may  have  25  centimeters  (9.8  inches)  in 
excess  of  the  projection  allowed  for  the  cornices,  balconies  and  entablatures 
upon  which  they  are  fixed. 

Art.  26.  Roof  ornaments,  such  as  finials  on  dormers,  open  crestings 
and  galleries,  may  not  project  beyond  the  arc  of  a  circle  concentric  with 
that  of  the  "limiting  cross  section"  and  of  which  the  radius  exceeds  that 
of  the  latter  by  the  permitted  projection  of  the  upper  part  of  the  facade. 

In  their  total,  the  size  of  the  crowning  members  of  dormers  may  not 
exceed  two-thirds  of  the  frontage  of  the  facade  of  the  building,  after  de- 
ducting the  crowning  members  of  the  corbeled-out  structures  projecting 
over  the  public  way,  as  provided  for  in  this  decree. 

For  the  crowning  members  of  the  corbeled-out  constructions,  the  in- 
crease of  radius  referred  to  above,  may  equal  twice  the  maximum  projec- 
tion permitted  for  the  upper  part  of  the  facades,  provided  that  spaces  of 
habitable  rooms  do  not  exceed  the  limits  of  the  concentric  arc  referred 
to  above. 

In  the  three  above  cases,  the  circular  arcs  are  prolonged  by  their  tangents 
at  45  degrees. 


136  APPENDIX  B 


For  corbeled-out  constructions  those  portions  of  the  crowning  members 
which  project  above  the  established  line  of  the  roof  may  not  exceed  in  width 
one-third  of  the  portion  on  the  facade  proper. 

■y 
Third  Section.    Projection  of  Objects  not  Forming  an  Integral 

Part  of  the  Structure 

(This  section  consists  of  ten  articles  and  deals  with  store  fronts,  grilles, 
signs,  marquises,  lights,  rain-water  conductors,  etc.) 

Fourth  Section 
(This  contains  one  article,  dealing  with  temporary  structures.) 

TITLE  HI 
SPECIAL  REQUIREMENTS 

(This  contains  seven  articles,  dealing  with  special  cases,  two  of  which 
are  of  sufficient  interest  to  be  given  in  full.) 

Art.  38.  Existing  projections  beyond  the  limits  fixed  by  the  present 
decree  may  not  be  repaired  even  in  part,  or  restored,  except  within  the 
limits  established  herein. 

Except  that  in  certain  cases,  ancient  objects  of  archeological  or  artistic 
interest,  may  be  repaired  by  permission  of  the  prefect  of  Seine. 

Art.  42.  The  prefect  of  the  Seine  may,  in  the  case  of  private  con- 
structions having  a  monumental  character,  or  for  purposes  of  art,  science, 
or  industry  and  with  the  approval  of  the  "conseil  general  des  batiments 
civils"  and  the  minister  of  the  Interior,  authorize  exceptions  from  the 
present  decree  relative  to  the  height  of  buildings. 

He  may  also,  following  the  same  procedure,  authorize  exceptional  pro- 
jections for  buildings  having  a  monumental  character. 

Art.  44.    The  decrees  of  July  22,  1882,  and  July  23,  1884,  are  repealed. 


APPENDIX    C 


REGULATIONS  OF  SOME  OF  THE  PRINCIPAL  CITIES  OF  THE 

UNITED  STATES  AND  CANADA  GOVERNING  THE 

HEIGHT  OF  BUILDINGS 

Note.  —  The  regulations  given  are  those  which  apply  to  buildings  of 
fireproof  construction.  Limitations  of  height  for  non-fireproof  buildings 
primarily  imposed  to  decrease  the  fire  hazard,  rather  than  to  prevent  en- 
croachments upon  the  light  and  air  of  the  public  streets,  are  not  included 
in  this  list. 

All  of  the  regulations  given  are  those  in  force  in  1911. 

Boston.  —  Since  1891  the  height  of  buildings  in  all  cities  of  Massachu- 
setts has  been  limited  to  125  feet. 

Grain  elevators,  coal  elevators,  and  sugar  refineries  are  excepted,  and 
steeples,  domes,  towers  and  cupolas  are  not  included  within  the  125  feet 
limit. 

In  Boston  this  limit  of  height  is  subject  to  a  further  restriction  of  2§ 
times  the  width  of  the  street,  so  that  on  streets  of  less  than  fifty  feet  in 
width  the  height  must  be  less  than  125  feet. 

The  maximum  height  of  125  feet  is  furthermore  only  permitted  in  those 
portions  of  the  city  in  which  the  greater  part  of  the  buildings  are  used  for 
business  or  commercial  purposes.  The  boundaries  of  these  portions  have 
been  determined  by  a  commission  appointed  for  the  purpose  and  the  areas 
within  them  are  known  as  "District  A." 

The  remainder  of  the  city,  comprising  much  the  larger  part  of  its  area, 
is  known  as  "District  B"  and  within  this  district  the  limitations  of  height 
are  as  follows: 

On  streets  of  64  feet  in  width,  or  less,  the  limit  is  80  feet. 

On  streets  exceeding  64  feet  in  width  the  height  may  be  equal  to  1  \  times 
the  width  of  the  street  but  may  not  exceed  100  feet.     Furthermore  a 

137 


138  APPEXDIX  C 


height  of  80  feet  may  not  be  exceeded  unless  the  width  of  the  building  on 
each  and  every  public  street  on  which  it  stands  is  at  least  one-half  its 
height. 

In  addition  to  these  general  regulations  there  are  other  special  restric- 
tions, as  follows: 

On  certain  streets  in  the  vicinity  of  the  state  capitol  the  limit  of  height 
is  70  feet.  Upon  a  portion  of  Commonwealth  Avenue  (one  of  the  prin- 
cipal parkways  of  the  city)  the  limit  of  height  is  70  feet. 

This  latter  restriction  is  imposed  by  the  Park  Commissioners,  who  have 
the  power  to  impose  such  restrictions  on  any  parkway,  boulevard  or  public 
way  bordering  on  a  park,  within  the  city. 

Winnipeg.  — Xot  exceeding  120  feet. 

Montreal.  —  Xot  exceeding  130  feet  nor  over  ten  stories. 

Portland.  — Xot  exceeding  160  feet  nor  over  ten  stories. 

Baltimore.  — Xot  exceeding  175  feet,  except  by  special  permission  of  the 
City  Council. 

Cleveland.  — Xot  exceeding  200  feet,  nor  more  than  i\  times  the  width 
of  the  street  nor  more  than  five  times  the  width  of  the  base. 

Chicago.  — Xot  exceeding  260  feet.  (After  July  n,  1911,  not  exceeding 
210  feet.) 

St.  Louis.  —  The  limit  of  height  for  all  buildings  other  than  hotels  and 
office  buildings  is  2§  times  the  width  of  the  street,  with  a  maximum  limit 
of  150  feet. 

The  limit  of  height  for  hotels  is  206  feet. 

The  maximum  limit  of  height  for  office  buildings  is  250  feet,  but  this 
height  is  not  permitted  unless  the  building  covers  at  least  one-half  of  the 
city  block  in  which  it  is  built,  has  frontages  on  at  least  three  different 
streets,  and  fulfills  certain  stringent  requirements  in  regard  to  fire  protec- 
tion. Otherwise  the  limit  of  height  for  office  buildings  is  the  same  as  that 
for  hotels,  viz.,  206  feet. 

St.  Paul.  —  Xot  exceeding  250  feet  nor  over  twenty  stories. 

Toronto.  —  Xot  over  five  times  the  least  horizontal  dimension  of  the 
building. 

Seattle.  —  Xot  over  five  times  the  least  dimension  of  the  base. 

Indianapolis.  —  Xo  limit,  except  in  the  neighborhood  of  the  city  monu- 
ment, where  a  limit  of  86  feet  is  imposed. 


APPENDIX  C  139 


Cincinnati.  —  No  limit. 
Detroit.  —  No  limit. 
Hartford.  —  No  limit. 
Milwaukee.  —  No  limit. 
Minneapolis.  —  No  limit. 
New  York.  —  No  limit. 
Philadelphia.  —  No  limit. 


COLUMBIA  UNIVERSITY  LIBRARY 

This  book  is  due  on  the  date  indicated  below,  or  at  the 
expiration  of  a  definite  period  after  the  date  of  borrowing, 
as  provided  by  the  rules  of  the  Library  or  by  special  ar- 
rangement with  the  Librarian  in  charge. 


•* 
DATE  BORROWED 

DATE  DUE 

DATE  BORROWED 

DATE  DUE 

JUN  3  1  '40 

?m 

%  4  i@#- 

FEB 

2  8  1947 

'■■—. 

i:     :*. 

JUL 

f\\V 

0CT1 

71949 

C28'Z39)M100 

^ 


RA9  67  At5 

Atkinson 


